Copyright: Andre Schoorl, 1997


Table of Contens

Table of Contents

1.   Introduction

2.   Miscellaneous Questions

3.   Questions about ROM versions

4.   Questions about the Operating System and Using the HP

5.   Questions about cards, data transfers, batteries, and hardware

6.   Questions about programs

7.   Questions about programming and advanced user functions

8.   Appendix A: Various Useful Functions

9.   Appendix B: GX Specific Information

10. Appendix C: Details of Bugs

11. Appendix D: Hardware Additions

12. Appendix E: Where to get HP48 Programs

13. Contributors


Introduction

1. Introduction

1.1 Overview

1.2 This FAQ in Other Formats

1.3 Translations of this FAQ


Introduction

  1.  Introduction

  This FAQ is maintained by Andre Schoorl <aschoorl@engr.uvic.ca>.

  It was previously maintained by Keith Maddock, and was originally

  compiled by Darryl Okahata.  Many thanks to both for their time and

  contributions!

  I rely on your input in order to keep this FAQ up to date.  If you

  have any suggestions or updates, feel free to mail them to me.


Overview

  1.1.  Overview

  The purpose of this FAQ is to provide answers to commonly asked

  questions about the Hewlett Packard HP48 family of scientific

  calculators.  This list contains information which has not necessarily

  been verified, and is not guaranteed to be correct.  It has been

  compiled from various postings in the newsgroups comp.sys.hp48 and

  comp.sys.handhelds, as well as other sources.  In particular, some

  parts were taken from older HP48 SX "FAQ Lists".

  For some questions, there may be different answers for each calculator

  (G/GX vs. S/SX).  In this case S/SX specific information is preceeded

  by an "SX:" on the left margin of the first line of each S/SX specific

  paragraph.  G/GX information is denoted by a "GX:" in the same place.

  If a paragraph has no notation, then it is valid for all versions.


This FAQ in Other Formats

  1.2.  This FAQ in Other Formats

  This document was made using the SGML-Tools package and is available in

  ASCII, HTML, and PostScript versions.  All versions come from the same

  source, and are thus updated simultaneously.

  The URL for the HTML version is: <http://www.engr.uvic.ca/~aschoorl/faq/>.

  The other formats are also available here in separate zip files.

  The PostScript version is formatted for U.S. Letter paper, but I can

  also create PostScript for Legal size paper.  Furthermore, I can

  create DVI, LaTeX, Lyx, Info, and RTF forms of the FAQ.  These are

  currently available on request but if demand warrants I will consider

  including one or more of them with the standard FAQ package.

  Text only versions of the FAQ will be posted to the newsgroup

  comp.sys.hp48 as needed (usually every two weeks).  Also, remember

  that all official FAQs (including this one) are mirrored at

  <ftp://rtfm.mit.edu/>.

  Furthermore, it is posted to comp.answers and news.answers.

  I will sign all text versions with PGP using the following key for authenticity,

  and provide MD5 Checksums for the remaining files.

  You can get a copy of this public key through the URL above.

Type	bits/keyID	Date	User ID
pub	2048/3CD1B675	1995/01/19	Andre P. Schoorl <aschoorl@engr.uvic.ca>

  Key fingerprint =  33 BF 8C EC A1 2B 13 11  AE A3 FE 3E 00 A1 31 4D

  Alternatively, you can download the FAQ at one the following locations:

  North America:

     •  <ftp://ftp.cis.com/pub/hp48g/uploads/>

     •  <ftp://ftp.cis.com/pub/hp48g/documentation/>

     •  <ftp://oprfhs.org/pub/hp48/incoming/>

  Europe:

     •  <ftp://ftp.stud.fh-heilbronn.de/pub/hp48/incoming/>

     •  <ftp://ftp.stud.fh-heilbronn.de/pub/hp48/info/FAQ/>


Standard Generalized Markup Language


         Pretty Good Privacy


Translations of this FAQ

  1.3.  Translations of this FAQ

  These translations may not be as up to date as the main FAQ, but

  should still be useful for international users who are more

  comfortable with their native language.

  Spanish:

     •  <http://www.ing.udec.cl/~gsilvac/hp48.htm> by Guido Silva Carvajal


Miscellaneous Questions

2. Miscellaneous Questions

2.1    I'm a novice, and I have some questions. Where should I start?

2.2    What Usenet Newsgroups are there for the HP48?

2.3    What are some good FTP sites for the HP48?

2.4    Are there any good WWW links for HP48 stuff?

2.5    Is there an HP48 IRC Channel?

2.6    How can I search for a specific HP48 file?

2.7    What are good places to buy HP48's and accessories?

2.8    Are there any CD-ROMs with HP48 software?

2.9    Are there an HP48 Emulators?

2.10   Is the HP48 Allowed on SATs, AP, or ACT Tests? (U.S.)

2.11   When is the next HP coming out? Should I wait?

2.12   How does the HP48 compare with other calculators?

2.13   What is the Universal Font Library (UFL)?

2.14   Are there any PC fonts for the HP48?


I'm a novice, and I have some questions.

  2.1.  I'm a novice, and I have some questions.

           Where should I start?

  Start by perusing the HP48 manuals. You'd be amazed how many

  questions can be answered if you read the manuals.

  SX:

        Earlier HP48 S/SX manuals came in two volumes. The first volume

        dealt with operating instructions, and the second volume dealt

        with programming.  Later HP48 S/SX manuals combined these two

        volumes into one.

  GX:

        HP48 G/GX models come with a one-volume owners manual that

        covers all of the non-programming aspects of the calculator.

        An Advanced User's Reference (AUR) is available that covers

        programming aspects.  It is highly recommended. They also come

        with a Quick Start Guide, a guided tour of some of the HP48's

        capabilities.

  Also, look over the section "Answers to Common Questions", in Appendix

  A of the manual.  If you have a two-volume manual, it will be in volume II.


What Usenet Newsgroups are there for the HP48?

  2.2.  What Usenet Newsgroups are there for the HP48?

  comp.sys.hp48

        Primary HP48 newsgroup.

  comp.sys.handhelds

        Occasionally, HP48 information is posted to this newsgroup.

  comp.sources.hp48

        This newsgroup has been dead for years, but was once a moderated

        group for HP48 Programs.

  Articles posted to the newsgroup comp.sys.hp48 are archived at

  <ftp://wuarchive.wustl.edu/usenet/comp.sys.hp48/>.

  Articles are archived by year and month, with a general index covering

  approximately the past two years.

  The AltaVista search engine at <http://www.altavista.digital.com>

  also accesses these archives (for a Usenet search), and automatically

  uncompresses any relevant articles you may select.

  DejaNews <http://www.dejanews.com/> is another fast Usenet

  archiver/searcher, with many extra features such as Author profile and

  article search.

  Another good way to find HP48 posts is through one of the various

  search engines available on the web.  For example, Netscape, Lycos,

  and Magellan and others all seem to be able to find Usenet articles on

  the HP48. The search may even find articles that have long since

  expired from your local news server!


What are some good FTP sites for the HP48?

  2.3.  What are some good FTP sites for the HP48?

  Many HP48 programs can be found on the following FTP sites:

  •  <ftp://ftp.cis.com/pub/hp48g/>

  •  <ftp://hpcvbbs.external.hp.com/dist/>

  •  <ftp://oprfhs.org/pub/hp48/>

  •  <ftp://wuarchive.wustl.edu/systems/hp/hp48/>

  For a list of other HP48 FTP sites, see Appendix E-2.


Are there any good WWW links for HP48 stuff?

  2.4.  Are there any good WWW links for HP48 stuff?

  Rather than list out a long list of HP48 related WWW resources, here

  is a single HP48 Page which contains links to other HP48 pages:

  •  <http://www.gmi.edu/~madd0118/hp48/>


Is there an HP48 IRC Channel?

  2.5.  Is there an HP48 IRC Channel?

  Yes, try connecting to an EFNet server and join channel #hp48.  Many

  of the most knowledgeable HP48 users frequent it, making it a nice

  place to get your questions answered. There are even two IRC robots

  (hp48b and RPL) on the channel, where hp48b is a file server. The

  following information will get you started:

  First, download an appropriate IRC client.  Here are some links:

     UNIX client

     • <ftp://cs-ftp.bu.edu/irc/clients/>

        <ftp://ftp.acsu.buffalo.edu/pub/irc/>

        <ftp://ftp.funet.fi/pub/unix/irc/>

        <ftp://coombs.anu.edu.au/pub/irc/>

        <ftp://ftp.informatik.tu-muenchen.de/pub/comp/networking/irc/clients/>

     EMACS elisp

     • <ftp://cs-ftp.bu.edu/irc/clients/elisp/>

        <ftp://ftp.funet.fi/pub/unix/irc/Emacs/>

        <ftp://ftp.informatik.tu-muenchen.de/pub/comp/networking/irc/clients/>

        <ftp://cs.hut.fi/pub/irchat/>

     X11 client

     • <ftp://catless.ncl.ac.uk/pub/>

        <ftp://ftp.aud.alcatel.com/tcl/code/>

     NeXTStep client

     • <http://www-personal.engin.umich.edu/~premise/foundation/encircle/>

     VMS client

     • <ftp://cs-ftp.bu.edu/irc/clients/vms/>

        <ftp://coombs.anu.edu.au/pub/irc/vms/>

        <ftp://ftp.funet.fi/pub/unix/irc/vms/>

        <ftp://ftp.informatik.tu-muenchen.de/pub/net/irc/>

     REXX client for VM

     • <ftp://cs-ftp.bu.edu/irc/clients/rxirc/>

        <ftp://ftp.informatik.uni-oldenburg.de/pub/irc/rxirc/>

        <ftp://ftp.informatik.tu-muenchen.de/pub/net/irc/VM/>

        <ftp://coombs.anu.edu.au/pub/irc/rxirc/>

        <ftp://ftp.funet.fi/pub/unix/irc/rxirc/>

     MSDOS

     • <ftp://cs-ftp.bu.edu/irc/clients/pc/msdos/>

        <ftp://ftp.funet.fi/pub/unix/irc/msdos/>

     Microsoft Windows

     • <ftp://cs-ftp.bu.edu/irc/clients/pc/windows/>

        <ftp://ftp.demon.co.uk/pub/ibmpc/win3/winsock/apps/wsirc/>

        <ftp://ftp.demon.co.uk/pub/ibmpc/win3/winsock/apps/mirc/>

     OS/2

     • <ftp://cs-ftp.bu.edu/irc/clients/pc/os2/>

     Macintosh

     • <ftp://cs-ftp.bu.edu/irc/clients/macintosh/>

        <ftp://mirrors.aol.com/info-mac/comm/>

        <ftp://ftp.funet.fi/pub/unix/irc/mac/>

        <ftp://ftp.ira.uka.de/pub/systems/mac/>

  Second, find a working EFNet server (refer to list below) and join

  #hp48.

  This list is also available via ftp at

     • <ftp://ftp.comco.com/pub/irc/server-list-current>

irc.cadvision.ab.ca	207.34.96.2	Canada
irc2.magic.ca	199.166.230.68	Canada
irc.magic.mb.ca	204.112.14.42	Canada
portal.mbnet.mb.ca	130.179.16.140	Canada
..	204.112.178.12	..
irc.mcgill.ca	132.206.27.12	Canada
irc.cs.mun.ca	134.153.1.2	Canada
elk.nstn.ca	137.186.128.21	Canada
irc.vianet.on.ca	204.50.187.50	Canada
irc.polymtl.ca	132.207.4.8	Canada
irc.yorku.ca	unresolvable	Canada
irc02.irc.aol.com	152.163.193.130	USA, Virginia
irc.blackened.com	192.195.240.63	USA, Arizona, Tucson
irc2.blackened.com	192.195.240.139	USA, Arizona, Tucson
irc.mindspring.com	204.180.131.3	USA, GA, Atlanta
irc.neosoft.com	206.109.6.193	USA, Texas
irc-1.netcom.com	unresolvable	USA, California
irc-2.netcom.com	unresolvable	USA, California
irc2-1.netcom.com	unresolvable	USA, California
irc2-2.netcom.com	unresolvable	USA, California
ircd.netcom.com	206.217.29.1	USA, California
irc.nwlink.com	199.242.23.65	USA, WA, Bellevue
irc.primenet.com	206.165.111.241	USA, Arizona
irc.psinet.com	38.9.15.2	USA, VA, Herndon
irc.sprynet.com	165.121.1.46	USA, WA, Seattle
irc.visi.com	204.73.178.15	USA, MN, Minneapolis
irc.voicenet.com	207.103.0.200	USA, PA, Ivyland
mangky.eecs.berkeley.edu	128.32.240.161	USA, California, Berkeley
irc.ecn.bgu.edu	143.43.32.201	USA, Illinois
azure.acsu.buffalo.edu	128.205.7.6	USA, New York
irc.cs.cmu.edu	128.2.203.89	USA, PA, Pittsburgh
irc.colorado.edu	128.138.129.31	USA, Colorado
organ.ctr.columbia.edu	128.59.68.35	USA, New York
red-dwarf.cit.cornell.edu	132.236.56.9	USA, New York
irc.law.emory.edu	170.140.50.195	USA, GA, Atlanta
irc.cs.rpi.edu	128.213.4.197	USA, New York
irc.rutgers.edu	165.230.224.131	USA, New Jersey
irc.stanford.edu	36.55.0.50	USA, California
anarchy.tamu.edu	128.194.12.120	USA, Texas, College Station
irc.ucdavis.edu	128.120.101.102	USA, California
irc.uci.edu	128.195.7.77	USA, California, Irvine
irc.uiuc.edu	192.17.7.229	USA, Illinois
akane.umd.edu	129.2.8.149	USA, MD, College Park
pegasus.ccs.itd.umich.edu	141.211.26.105	USA, Michigan
irc.umn.edu	160.94.196.193	USA, Minnesota
piglet.cc.utexas.edu	128.83.42.61	USA, Texas, Austin
becker1.u.washington.edu	140.142.12.67	USA, Washington
irc.eng.yale.edu	130.132.20.72	USA, Connecticut
efnet.evitech.fi	195.148.144.5	Finland
irc.ec-lille.fr	193.51.52.49	France
irc. tau.ac.il	132.66.16.5	Israel
irc.technion.ac.il	132.68.1.11	Israel
irc.ibm.net.il	192.115.72.164	Israel
irc.ais.net	199.0.154.13	USA, Illinois
irc-ais.ais.net	199.0.154.23	USA, Illinois
irc.best.net	206.86.8.69	USA, CA, Mountain View
opus.bridge.net	204.253.4.200	USA, Florida, Miami
irc.cdc.net	205.217.64.5	USA, TN, Chattanooga
irc.cerf.net	192.215.245.12	USA, CA, San Diego
irc2.cerf.net	192.215.245.13	USA, CA, San Diego
irc.concentric.net	206.173.136.204	USA, Michigan, Bay City
irc-2.concentric.net	unresolvable	USA, Michigan, Bay City
irc.digex.net	205.197.247.96	USA, Maryland
irc.frontiernet.net	204.168.13.13	USA, NY, Rochester
irc.gate.net	199.227.0.17	USA, Florida
irc.hookup.net	165.154.1.1	Canada, Ontario
ircd.idt.net	169.132.8.100	USA, NJ, Hackensack
irc.ionet.net	208.129.64.25	USA, OK, Okc
irc.lightning.net	206.148.240.14	USA, NY, Mineola
irc.mcs.net	192.160.127.90	USA, Illinois
irc.mo.net	205.164.64.254	USA, Missouri
irc.nol.net	206.126.32.100	USA, TX, Houston
irc.phoenix.net	207.43.0.134	USA, Texas, Houston
irc2.texas.net	206.127.26.3	USA, Texas, San Antonio
ircd.texas.net	206.127.0.130	USA, Texas, San Antonio
irc.voyageronline.net	206.155.203.3	USA, TN, Chattanooga
irc.homelien.no	194.19.4.206	Norway
eff.org	204.253.162.3	USA, San Francisco
irc.io.org	198.133.36.153	Canada, Toronto
irc.sintercom.org	203.120.37.250	Singapore
irc.gd.gu.se	130.241.152.48	Sweden
irc.df.lth.se	194.47.252.146	Sweden
irc.bofh.co.uk	164.11.100.27	United Kingdom
efnet.demon.co.uk	194.159.255.9	United Kingdom


How can I search for a specific HP48 file?

  2.6.  How can I search for a specific HP48 file?

  If you know the all or part of the filename of an HP48 program, you

  can use the proper InterNET search services instead of bothering all

  the readers of the newsgroup.  The following server is especially

  good, it seems to find HP48 files from just about anywhere.

       <http://ftpsearch.unit.no/ftpsearch>


What are good places to buy HP48's and accessories?

  2.7.  What are good places to buy HP48's and accessories?

  Educalc:

        Educalc carries a complete line of HP calculators and

        accessories. They also sell used HP48's, and buy them as trade

        ins. To get a free catalog, call them. Their WWW page is

        <http://www.educalc.com/> or you can e-mail them at

        <rebecca@educalc.com>

Toll Free Order:	(800)-677-7001	\___ Orders and Customer Service
Toll Order:	(714)-582-2637	/       8-5, M-F, West Coast Time
Credit Card Order:	(800)-535-9650	ext. 9162 (all hours, all days)
FAX orders:	(714)-582-1445
Technical Support:	(714)-582-2637
          "Para ayuda en Espanol - pregunte por Irma"

  Elek-Tek:

        Elek-Tek seems to only carry HP name brand products. Their

        prices may be slightly cheaper than EduCalc, but they don't carry

        non "HP brand" products (such as RAM cards), that are much

        cheaper than HP brand ones.

Toll Free: (800)-395-1000	Order:         (708)-677-7660
Fax:         (708)-677-7168	Fax Orders: (708)-677-1081

  HP48 Head Quarters:

        You can order HP48's and accessories online at

        <http://www.hp48.com/>

  X-Philes CD-ROM:

        There is a CD-ROM called the X-Philes on the market that

        includes many HP48 files. See the next question for more

        details.

  Office Max:

          Toll Free: (800) 788-8080

  Wholesale Products:

        This is another company on the web that sells HP handhelds,

        including the HP48.  Their address is

        <http://www.wholesaleproducts.com> or you can mail inquiries to

        <wholesal@shore.net>

Wholesale Products

One Forbes Street

Box 9134

Chelsea, Massachusetts  02150-9134

Toll Free Order Number (USA/CANADA):	1-800-574-7253
24 Hour Fax Order Line:	1-617-438-8307
E-Mail (INQUIRIES ONLY):	wholesal@shore.net
Non-USA/CANADA:	1-617-884-1110

  Others:

          Executive Photo and Electronics

          120 West 31st St., New York, NY 10001-3485

          Tel: 800-223-7323 or 212-947-5295

          Fax: 212-239-7157

          Global Connections Incorporated (formerly Connection Point, Inc.)

          50 South River Street, Suite 105, Janesville, WI 53545

          Tel: (608)-752-9548 or (608)-752-1537

          Oxford Educational Supplies (U.K.)

          Tel: 01869 343369 (mail order)

          Notes: No shipping charge for within U.K.

          Spectrum Office Equipment

          22 Stokes Croft Bristol (U.K.).

          0117 9428278

          Best (Western U.S., used to be La Belles) 1-800-950-2378

          Calculators Inc., Minneapolis, MN, U.S. (612) 866-8908

          Carrington, (800) 982-3731

          J&R Music World - Computer World 1-800-221-8180

          Office Depot (U.S. and Canada)

          Service Merchandise (East Coast U.S.)


Are there any CD-ROMs with HP48 software?

  2.8.  Are there any CD-ROMs with HP48 software?

  Yes, there are three CD-ROMs with HP48 software I know of:

    X-Philes:

        The X-Philes is a CD-ROM made by Synchron Data that contains

        most HP48 programs to date.  All together the CD-ROM contains

        over 21,000 files and more than 620 MB of information, mostly

        zipped.

        The HP48 sections contain 3194 files and make up 38.5 MB of the

        total.  This includes all of the EduCalc Goodies disks (aka Horn

        disks) 1 through 10.

        There are also files for HP95, Psion, TI-82 and TI-85

        calculators, as well as information and programs on:

        Jokes, Star Trek, Sports, Midi, History, Strange files,

        Conspiracy, Law and Business, Internet & Networks, Atari, BBS-

        Systems, Hardware, Computers, 3D-Objects, Anarchy, Hacking,

        Movies, X-Files, Music, Magazines, Science, UFO and Aliens,

        Occult, Security & Privacy, Amiga, Cyberspace, Subcultures,

        Radio, Virus hunting, Survival, Phreaking, PC utilities, Game

        cheats and levels, and Programming.

        The CD comes with easy to use Windows software for browsing and

        searching for keywords.  This software contains an upload

        feature that allows you to transfer programs directly to your HP

        (or modem) using X-Modem.

        More information on obtaining the X-Philes CD-ROM is at:

        WWW:  <http://www.algonet.se/~synchron/>

        E-Mail: <dt93tn@pt.hk-r.se>

        Regular Post:

          Synchron Data

          Tranbarsvagen 25:14

          372 38 Ronneby

          Sweden

    SHAREWARE Volume 1 for Hewlett-Packard:

        There is a CD-ROM by a German company called Yellow Computing

        named SHAREWARE Volume 1 for Hewlett-Packard.  It sells for DEM

        49.80 (U.S.$ 34.00), and is distributed from:

          Yellow Computing	Phone +49 7136 951143

          Computersysteme GmbH	Fax +49 7136 951111

          Postfach 1136

          D-74173 Bad Friedrichshall

          Germany

        This is the German company which offers PC <-> HP-48 transfer

        cables together with Windows software for transfering files (the

        "Transfile Win 48" package).

        The CD-ROM comes with a 16 page booklet in German and English which

        shows how to use the included Windows 3.1 transfer program (with program

        and catalogue files in both languages).

        It's sampled in Aug 95, pressed Oct 95 and contains about 85 MB of

        software for the HP48 SX/GX, 95LX, 100LX and 200LX; the Horn disks

        1 through 9, and about 710 additional HP-48 programs in the 9

        categories: Animation, Data, Games, Graphic, Programming, Maths,

        Memory, Science, Utility and Communications.  It also has about 200

        other unsorted, compressed HP48 files.  Decompression software is

        included.

        It's not an ISO CD-ROM, since it contains directories and files,

        whose names contain exclamation marks, hyphens and dollar signs.

        For more information, orders, and pricing send e-mail to:

        <info@yellow.de>

    Handheld HP CD-ROM Library:

        This collection contains 13,611 files for a total of 314 MB of

        compressed software for HP Handhelds.  The principal groups of

        this collection are:

        1. HP28C/S (up to 2.5 Mb) Applications, Games, Utils, Docs.

        2. HP48S/SX (up to 48 Mb) Applications, Business, Chemistry,

           Communications, Emulators, Games, Graphics, Math, Physics,

           Programming, Sound, Time, Utils, Docs.

        3. HP48G/GX (up to 40 Mb) Applications, Business, Chemistry,

           Communications, Games, Graphics, Math, Physics, Programming,

           Sound, Time, Utils, Docs, Sys-RPL.

        4. HP38G (up to 2 Mb) Applets, Applet Development Kit, Docs.

        Platform files total 30 MB, additional documentation is 18 MB,

        various collections including the Horn disks and SysRPL

        collection total 106 MB, and finally 58 MB of information from

        HP groups around the world.

        For more information, orders, and pricing send e-mail to

        <carles@idgrup.ibernet.com>


Are there an HP48 Emulators?

  2.9.  Are there an HP48 Emulators?

  A fully functional HP48 emulator by Eddie Dost called "x48" is

  available.  It runs in X-Windows on any Unix based operating system

  like Linux or Solaris.  However, it requires a ROM dump of an HP48 to

  run.  Of course, due to copyright laws such a ROM dump can not be

  distributed with the x48 package.

  Therefore, you must be the proud owner of an HP48 (S/SX or G/GX) in

  order to create your own ROM dump.  The emulator will look and act

  either like a S/SX or a G/GX, depending on what type of ROM dump you

  give it.  Further instructions are contained in the x48 package

  itself.  The latest version of x48 is available at

  <ftp://ftp.cis.com/pub/hp48g/uploads/x48-040.zip>

  There is also a shareware emulator for Windows called Win48.  It is

  written by Sebastien Carlier, and runs under either Windows 95 or NT.

  It offers many exciting features, including fast speed, saving of memory,

  direct loading of files onto the stack, and port 1 support.

  It supports both S/SX and G/GX ROM dumps, and comes with a "RomDump

  Wizard" to help you create one.

  The evaluation version, as well as more information is available at

  <http://www.geocities.com/CapeCanaveral/5948>

  The evaluation version has a time limit and memory limit which

  encourages you to register for a small fee.


Is the HP48 Allowed on SATs, AP, or ACT Tests? (U.S.)

  2.10.  Is the HP48 Allowed on SATs, AP, or ACT Tests? (U.S.)

  From: Jack Levy

  The S/SX/G/GX are allowed on the SAT's.  The S/SX/G/GX are allowed on

  the SAT II Math IIc test, but no calculators are allowed on any of the

  others.  The S/SX/G/GX are allowed on the AP Calculus exam.  However,

  only the S/SX are allowed on the AP Chem and AP Physics exams because

  the G/GX has the built in equation library.

  Update from: Sandler Rubin

  As of 1996, HP 48G calculators are allowed on the physics and

  chemistry APs, but only for the free response section.  All

  calculators are now banned on the multiple choice sections on the

  physics and chemistry APs.  As for calculus, the HP 48G is allowed on

  one half of the multiple choice and all of the free response.  The

  other half of the multiple choice on the calculus test must be

  completed without any calculator.

  These changes have occurred because the AP tests are now more

  conceptual and depend less on pure "number-crunching".  In the free

  response sections of the chemistry and physics tests, lists of

  important physics equations are include for student use which

  basically make the HP 48G EqLib redundant.

  Update from: John Goerzen

  After a lot of discussion with Candance Noble of ACT, they changed

  their policy to allow it only if the IR port is covered with opaque

  tape.  Their response follows:

  This notice is in response to questions ACT has received about

  acceptable calculators.  Please pass this clarification on to others.

  Effective Fall 1996, examinees may use calculators on the ACT

  Assessment and PLAN Mathematics Tests.  Students taking the ACT

  Assessment should review page 3 of Registering for the ACT Assessment.

  Students taking PLAN should review page 4 of the Planning Guide for

  Students and Parents.  All makes and models of calculators are

  acceptable -- including programmable calculators and hinged

  calculators with mathematical formulas printed by the manufacturer on

  the inside flap -- provided the calculator does not have any of the

  unacceptable features specified in the ACT publications noted above

  and further clarified below.  Examinees using unacceptable calculators

  will be dismissed from testing.

  The following information is provided to help students select an

  acceptable calculator if they choose to use one on the ACT Assessment

  or PLAN Mathematics Test.

  • POCKET ORGANIZERS, HANDHELD OR LAPTOP COMPUTERS

  • ELECTRONIC WRITING PADS/PEN INPUT DEVICES

  • PAPER TAPE

  • NOISE

  • WIRELESS COMMUNICATION

  • POWER CORD


All such devices are prohibited.


Such models are readily recognizable due to the pen or stylus

used to input data.  All such devices are prohibited.

The term QWERTY derives from the first six letter keys (left to

right) of the top row of typewriters, personal computers, most

handheld and laptop computers, pocket organizers, and

specialized calculators.  All models with QWERTY keyboards are

prohibited.


If a calculator has a feature that provides paper output, the

paper must be removed to make the calculator acceptable.


Calculators that have a "talking" or audio feature are

acceptable in a group testing situation only if the sound

feature has been turned off.


Calculators that can communicate (transfer data or information)

wirelessly with other calculators can be recognized by the

"window" or infrared data port on the top edge of the calculator,

similar to one on a television remote control.  Such calculators

are acceptable only if the wireless transfer capability is disabled

by placing opaque material (such asmasking tape) over the infrared

data port.


If a calculator can run on either battery or electrical cord,

the electrical cord must be removed to make the calculator

acceptable.


When is the next HP coming out?  Should I wait?

  2.11.  When is the next HP coming out?  Should I wait?

  From: Matt Willis

  No-one really knows for sure.  There have been rumours for years now.

  But so far, that's all they have been - rumours.  Those who know,

  won't talk.

  Of course, people will speculate.  But the people who work for HP

  won't say a thing.  While it may be a point of professionalism, it's

  probably also something that they can't do, contractually.  So it's

  rude to ask.

  Why do they do this?  It makes sense, from HP's perspective.  HP,

  unlike some other calculator companies, waits until a product is ready

  before marketing it.  For example, the HP38 was a surprise.  Think

  what would happen to sales if HP announced a new calculator was coming

  out in 6 months.

  Even if HP announced a new calculator tomorrow, I don't think I would

  upgrade right away.  Why?  Well, when the 48 G/GX came out, it went

  through revisions K, L, M, P and then R (to check what version of G/GX

  you have, type VERSION).

  The next calculator, by Murphy's Law, is bound to initially have just

  as many bugs when it first comes out.


How does the HP48 compare with other calculators?

  2.12.  How does the HP48 compare with other calculators?

  From: Chin-Yu Hsu <chinyu@voyager.bxscience.edu>

  What are the differences between the HP48 and the TI?

  Before listing the differences, I wish to let you know that the HP48

  has much more functionality than the TI's. However, these additional

  functions are usually of no help in high school than the TI. Instead,

  they are only helpful in college depending on the course you take. The

  TI is probably a better choice on tests in high school since it is

  easier to use (to most people) and does calculations faster (because

  it offers speed at the expense of the higher precision of the HP48).

  Please note that the HP also offers the HP38 which is more comparable

  to a TI-82.

  Also, you should realize that if you want support for the graphing

  calculator, the HP48 is the one to get. Although you can get support

  from Texas Instrument (by phone and by web), and also by teachers in

  school, you can get support for the HP48 from a larger group in the

  world. There are far more web sites related to the HP48 than to the TI

  graphing calculators. Also, the HP48 has its own newsgroup and its own

  IRC channel (usually up 24 hours a day and maintained by a bot that

  can send you programs at your request).  Please note that although the

  calculation and graphing capabilities may not be available for a

  particular calculator, you can usually download a program that extends

  such a capability to it.

  If you find that part of the information below is incorrect, please

  tell me about it. You may need to provide additional proof, if I am

  unable to confirm it.  Any additional information on the TI-92 is

  helpful because much about it is still a mystery.

  General Differences:

Calculator	HP38	HP48(2)	TI-82(3)	TI-85	TI-92
List Price(4)	$109.00	$135.00/?	$125.00	$135.00	$250.00
Available Mem.(5)	32KB	32/128KB	28.2KB	28.2KB	70.0KB
Batteries Req.(6)	???	3AAA	4AAA+1	4AAA+1	4AAA+1
Plug-in Cards	No	Yes(7)	No	No	No
Infrared Transmit	Yes	Yes(8)	No	No	No
Wire Transmit	Yes	Yes	Yes	Yes	Yes
Cal-to-PC trans(9)	Yes	Yes	Yes	Yes	Yes
Overhead display	Yes	Yes(10)	Yes	Yes	Yes
CBL support(11)	No	No*	Yes	Yes	Yes
QWERTY keys(12)	No	No*	No	No	Yes
Screen capture	Yes	Yes	via link	via link	via link
Screen Resolution	131x64	131x64	96x62	128x64	240x128
Character Display	22x8	22x8	16x8	21x8	?????

  Miscellaneous Functions:

Calculator	HP38	HP48(2)	TI-82(3)	TI-85	TI-92
Simple Eq. Solver	Yes	Yes	No	Yes	Yes
Simult. Eq. Solver	?????	Yes	No	Yes	?????
Poly. Root Finder	No limit	No limit	No	30th order	Yes
# of matrices	10	No limit	5	No limit	?????
max matrix size(12)	No limit	125x125	15x15	30x30	?????

  Graphing Functions:

Calculator	HP38	HP48(2)	TI-82(3)	TI-85	TI-92
Simultaneous Graph	Up to 10	No limit	Up to 10	Up to 99	Up to 99
Zoom features	14	15	13	15	?????
Graph Tracing	Yes	Yes	Yes	Yes	Yes
Fnc. Value Tables	Yes	No	Yes	No	Yes
Parametric Graphs	Yes	Yes	Yes	Yes	Yes
Polar Graphs	Yes	Yes	Yes	Yes	Yes
Recur. Seq. Graphs	Yes	Yes	Yes	Yes	Yes
Diff. Graphs	No	Yes	No	No	No
Conic Graphs	No	Yes	No	No	No
3-D graphs	No	7 types	No	No	Yes
Area under Curve	No	Yes	Yes	Yes	Yes
Extremum	Yes	Yes	Yes	Yes	Yes
Roots	Yes	Yes	Yes	Yes	Yes
Slopes	???	Yes	Yes	Yes	Yes
Tangent Lines	???	Yes	No	No	???

  Statistical Functions:

Calculator	HP38	HP48(2)	TI-82(3)	TI-85	TI-92
Scatter Graphs	Yes	Yes	Yes	Yes	Yes
X-Y line Graphs	No	No	No	No	Yes
Box-Whisker Plots	Yes	No	Yes	No	Yes
Histogram Plots	Yes	Yes	Yes	Yes	Yes
Regression Graphs	No	Yes	Yes	Yes	Yes
Bar Graphs	Yes	Yes	Yes	Yes	Yes
Truth Graphs	Yes	Yes	No	No	No

  Notes:

  1.  In the specifications, "no limit" usually means that it is limited by memory only.

  2.  There are four different HP48 calculators. There are the HP48S,

       HP48SX, HP48G, HP48GX. The S and SX models are older models, and no

       one would be getting them anymore since the G and then GX offer all

       the same features, but with additional enhancements to make the

       features easier to use. The G and the GX are also 40% faster than

       the S and SX models. There are only two differences between the G

       and the GX... The G has 32K of RAM, and no expandability, while the

       GX has 128K of RAM and the ability to have two additional plug in

       cards.

  3.  There is a new version of the TI-82, called the TI-83 which should

       be available soon. It offers all the features of the TI-82, except

       it has additional statistics and financial functions, as well as

       displaying a table and a graph side by side. Please note that this

       feature is not available on the HP48, but is available on the HP38.

       Also, the TI-83 has an equation solver like the HPs.

  4.  Cost for HP calculators does not include cables because they can

       transfer data via infrared. The price for TI's include the cables

       for linking one TI to another. Also, the HP48G's list price is

       $135.00, while the HP48GX's list price is $265.00.

  5.  The available memory listed for the HPs are slightly lower than the

       given values. The available memory for the HP48G is only 32 K. The

       HP48GX has 128K of available RAM, and is expandable to 4.5 megs!

  6.  The batteries used by these calculators are AAA batteries.

       Rechargeable batteries are not recommended because they have a much

       lower life span than alkaline batteries. The TI's require an additional

       CR1616 battery to retain its memory power. The HP's do not need this

       additional battery, but once you take out the AAA batteries, you have

       about 3 minutes to replace them with new ones before it loses its memory.

       The RAM cards for the HP48GX requires an CR1616 battery, however,

       if you plan to store it outside of the HP.

  7.  Only the HP48GX support plug-in cards. The HP48G doesn't.

  8.  If you are thinking of getting the HP's to cheat on tests because

       of the infrared capability, forget about it. The infrared receivers

       on the HP's only have a maximum range of THREE inches

       (The HP's transmitter has a longer range, up to several feet, but

       that will not help at all unless you are using it as a remote control to

       watch TV, or you are sending to an infrared device connected to an

       AC power source, such as the HP LaserJet 5 printers).

  9.  The Calculator to PC (or MAC) requires additional cable and

       software. For the HP, you only need to get the cable, which can be

       made from standard computer parts (a DB-9 and CD cable totaling

       about $15). No additional software is needed because you can use

       any communications program of your choice.  For the TI, you can

       either need to purchase a proprietary software and cable for about

       $60 to $80 at stores or you can download the software free at TI's

       web site, and try to make your own cable.  The same type of package

       is available from HP, but offers programming tools and debuggers,

       and costs about the same price.

  10. The overhead display unit for overhead projectors is available only

        for the HP48GX because the HP48G does not have the available

        extension slot to install the necessary interface card.

  11. The CBL stands for Computer Based Laboratory. It is created by TI,

        so it is not available on the HP of course. It simply allows you to

        collect data from different sources (sounds, temperature) at set

        intervals and can be analyzed on the calculator. The CBL unit's

        list price is approximately $225. Please note that there is a

        similar device for the HP-48, called the ADCM-48 which is a A-to-D

        converter and I/O interface that can read from four analog and four

        digital inputs.

  12. Please note that calculators with QWERTY keys are not allowed on

        the SAT exams. The HP calculators do not have QWERTY type

        keyboards, but you can connect it to your computer and have the

        keys from your computer echo on to the HP calculator after

        installing a simple freeware program.

  13. The maximum matrix size on the HP48G is only 42x42. The maximum

        matrix size on the HP48GX is 85x85, but it can be expanded to

        125x125 with the addition of an extra RAM card.


What is the Universal Font Library (UFL)?

  2.13.  What is the Universal Font Library (UFL)?

  The Universal Font Library, or UFL for short, is a set of libraries

  designed to help reduce the overhead of replacement fonts between a

  number of major HP48 programs.  The basic idea is instead of each

  program containing its own replacement font(s), the fonts are stored

  in a cetral library to save room.  In addition the UFL comes with a

  Font Maintenance Library (FMnt).

  If you use some of the programs in the Best Programs List, you may

  find you need a particular UFL library installed in order to use the

  program.  The UFL is maintained by Andre Schoorl and is distributed

  under the GNU General Public License.  For more information and to

  obtain the UFL package see <http://www.engr.uvic.ca/~aschoorl/ufl/>.


Are there any PC fonts for the HP48?

  2.14.  Are there any PC fonts for the HP48?

  Yes, there are several fonts on the Goodies Disks, as well as some TrueType

  fonts available at:

  <ftp://ftp.cis.com/pub/hp48g/uploads/48ttf.zip>


Questions about ROM versions

3. Questions about ROM versions

3.1   What does the SX/GX have that the S/G doesn't?

3.2   What is the difference between the HP48 G/GX and the HP48 S/SX?

3.3   How can I tell what ROM revision I have?

3.4   What bugs exist in the various versions of the HP48?

3.5   What is new with the revision "J" ROM? (S/SX)

3.6   What happened to ROM revisions G, H, I, O, and Q?

3.7   Can I upgrade my HP48 S/SX?

3.8   Can I upgrade my buggy GX to the latest ROM revision?

3.9   What's the latest ROM version?

3.10 Why would I buy a S/SX rather than a G/GX?


What does the SX/GX have that the S/G doesn't?

  3.1.  What does the SX/GX have that the S/G doesn't?

   SX:

      The HP48 S is the same as the HP48 SX except that the HP48 S

      does not have the two expansion slots of the HP48 SX.  This

      means that the HP48 S cannot be expanded and can only access 32K

      of memory, versus 288K for the HP48 SX (two 128K RAM cards).

      (Actually, there are third-party RAM cards that contain 256K or

      512K on a single card -- this memory is accessed via a bank-

      switching mechanism.)

   GX:

      The HP48 G is the same as the GX except for two differences.

      The GX has the 2 expansion ports, and also has 128K RAM built

      in, whereas the G only has 32K.

      If you plan on heavily using your calculator, you will probably

      find that 32K is not enough memory.  In fact, some of the best

      HP48 Programs will not even fit in this memory!


What is the difference between the HP48 G/GX and the HP48 S/SX?

  3.2.  What is the difference between the HP48 G/GX and the

        HP48 S/SX?

  The HP48 G/GX calculators are, basically, slightly faster (by 40%)

  versions of the HP48 S and HP48 SX calculators, with more features,

  such as 3D-plotting and a new forms-based interface.  Much of the HP

  Solve Equation Library card is now built-in.  See Appendix B-1 for a

  detailed list of GX features.

  Note, however, that the HP48 G/GX is different from the HP48 S/SX in a

  number of significant areas:

  1. The HP48 GX comes with 128KB RAM, as opposed to 32KB RAM in the

      HP48 SX.  The HP48 G still has 32KB RAM, however.  The HP48 G/GX

      also has twice the ROM (512K), compared the HP48 S/SX (256K).

  2. Much of the HP48 G/GX internals have changed, compared with the

      HP48 S/SX.  Unfortunately, this means that many programs written in

      assembly language or System RPL won't work on the HP48 G/GX.  This

      is especially true of any program that tried to access the display

      memory directly.

  3. The HP48 G/GX CPU runs at 4 MHz, instead of the 2 MHz used with the

      HP48 S/SX CPUs.  However, due to various overheads (memory bank

      switching, etc.), the speed increase between the S/SX and G/GX is

      less than 2 times.  G/GX throughput is approximately 40% faster.

  4. Slot 2 of the HP48 GX can access up to 32 ports (ports 2-33) by

      bank switching.  Each port is 128KB, for a maximum total of 4 MB in

      slot 2.


How can I tell what ROM revision I have?

  3.3.  How can I tell what ROM revision I have?

   GX:

      Type the command "VERSION".  Note that this command is not part

      of any key or menu, and so you must spell it out.

      Type #30794h SYSEVAL.  It returns a string, "HPHP48-x", where x

      is your ROM revision.  This works for both SX and GX.

   SX:

      1. Turn the calculator on (press ON and then release).

      2. Press ON again, and hold it down.

      3. While holding down the ON key, press and hold down the "D"

          key (the fourth white key in the top row).

      4. While holding down the "D" key, release the ON key.

      5. Release the "D" key.  The display should be blank, with the

          exception of three vertical lines (one down the centre, and

          one down each of the right and left sides).

      6. Press the backspace key (it says DROP and CLR over it).  A

          meaningless string of digits should appear in the top line of

          the display (mine says "705D9:1B8DA178E5A111B6" -- yours may

          be different).

      7. Press and hold down the EVAL key.  It should say something

          like the following, where the ? is an uppercase letter

          indicating the ROM version:

           Version HP48-?

           Copyright HP 1989

      8. Release the EVAL key.  Hold down ON and hit "C" (the third

          white key in the top row.  This is a general reset operation

          that returns the calculator to normal from the diagnostic

          stuff (which is where ON-D puts you).


What bugs exist in the various versions of the HP48?

  3.4.  What bugs exist in the various versions of the HP48?

  Rom: A

  • DEFINE rounds numbers in user-defined functions if STD is not

     the current display mode.

  • KGET on a zero length file from another machine will cause the

     calculator memory to be cleared.

  • NXEQ from the Graphics Environment with flag -3 set (SYM off in

     Modes) can overwrite the current equation with a number.

  • Displaying the clock in 24-hour format causes the one-digits for

     minutes to be incorrect in the alarm catalog.

  Roms: A-C

  • INV returns an incorrect result if used on an 8x8 or larger

     matrix.  To get around this problem, divide the identity matrix

     with the matrix to invert.

  Roms: A-D

  • Entering a symbolic complex number in polar form like (A,<B)

     (where < is really the funny little angle symbol), gives an

     expression in A and B that is wrong (the A and B are

     interchanged so A is the angle and B is the magnitude).

  • If the clock is displayed during an ARCHIVE via RS-232, there is

     a chance (not 100%) that calculator memory will be cleared,

     after the transfer.  The work-around is to turn the clock

     display off before doing the transfer.  Should your memory be

     cleared, you will have to restore the contents of memory from

     the archive.

  • TRNC and RND allow for an array in level 2 and a symbolic in

     level 1 of the stack. This allows you to put an array in a

     symbolic.  Example:  2 3  '7/8' RND returns 'RND(UNKNOWN,7/8'

  Roms: A-E

  • There's a bug in the EquationWriter that is "fixed" in the Rev J

     ROM.  See Appendix C-1 for details.

  Roms: E, J

  • BESTFIT: Occurs when a two dimensional array is stored in \GSDAT

     (SigmaDAT).  Pressing the BESTFIT softkey multiple times will

     leave a lot of useless reals on the stack.

  Rom: K

  • First HP48 G/GX released; includes various bugs affecting ports.

     Therefore, the version K ROM was only used in HP48 G units.

  Roms: K, L, M, P

  • XROOT Function fails when used with list processing unless X=Y.

     It does not corrupt memory.

     FIX: Preceed any XROOT which will use list processing with a

     SWAP

  Rom: L

  • Second HP48 G/GX released; fixed the port bugs.  This ROM

     version is that present in the 2,000 HP48 GXs sold at the ASEE

     conference for $90 apiece.

  Roms: L, M

  • HP48 GX may lose all of user memory when: clock is displayed, a

     library object is be stored in user memory, and a RAM card is

     lugged in to port one and merged with User Memory.  If all four

     of these conditions are present and the calculator is turned on

     when the clock is being updated by the system, a loss of all

     User Memory may occur.

     FIX: Just type the following in on your calculator:

   < RCLF -> f << -40 CF OFF f STOF >> >> 91.3 ASN

      Then turn on USER mode

  • EquationWriter/Character Picker Bug: If the size of the equation

     is greater than the regular size of the screen, calling the

     Character Picker in Equation Writer will garble the screen.

  • If you store an object into a port > 1 while there is a card

     installed in slot 1, the end-of-obj-sequence marker (00000) is

     written to port 1 instead to the destination port.  This will

     cause the 'Invalid Card Data' warning to pop up each power on

     after a while and, in addition, the memory of port 1 gets

     currupted (if it's writeable).  A temporary fix is to remove the

     card from slot 1 when changing the contents of the card in slot

     2.  However a better fix is to get the STOFIX library (available

     on GD#10 or at HPCVBBS, ~1K in size).

  Rom: M

  • Evaluating a tagged object which contains an operator (+, -, *, /, etc)

     as the second or subsequent character will leave an External and

     System Binary on the stack, as well as the original

     object.

  Roms: L, M, P

  • SigmaDAT: Put a NON-MATRIX in \GSDAT (SigmaDAT), run STAT

     graphical apps, edit \GSDAT.  Causes a crash.

  • XRECV will fail or cause memory lost if the amount of free RAM

     left is not about twice the size of the expected file.

     FIX: See FXRECV on GD 9.  Note that FXRECV is not necessary for

     Rom R, and in fact will not even run properly on Rom R.

  • RREF does not transform the matrix into Row Reduced Echelon Form

     correctly if the first column of the matrix consists entirely of

     zeros.  It may also return incorrect answers in some matrices.

     A work-around for this bug is to delete any leading all-zero

     column(s) from the matrix; this may be done using the Matrix

     Writer, via its -COL menu key, or via commands: 1 COL- DROP (to

     drop the first column).  Since row-reduction operations never

     change any all-zero column, you already know in advance that the

     given column(s) must be all-zero in the final result.

  Roms: L, M, P, R

  • portnum: { dir ... var } RCL/EVAL fails if portnum >= 2

  • Rotation rate to angular frequency conversion bug.  See Appendix C-2

     for a complete write-up.

  Roms: M, P, R

  • Repeated executions of FFT or IFFT can cause a memory loss.  The

     FFT and IFFT warmstart problem is caused by a CPU return stack

     overflow during interrupt handling.  The problem can only occur

     when the argument to FFT or IFFT is an MxN matrix with both M >

     1 and N > 1.  The vector argument case is immune to this

     problem.

     FIX: To compute the FFT of a matrix without risking warmstart,

     expand the matrix into its row vectors using ->ROW, compute the

     FFT of each row vector, collect the results into a matrix using

     ROW->, expand the matrix into its column vectors using ->COL,

     compute the FFT of each column vector, and finally collect the

     results into a matrix using COL->.  Except for less precision,

     this is the same result as would be obtained by applying FFT on

     the original matrix.  Use the same procedure with FFT replaced

     by IFFT to compute the IFFT of a matrix.

     Here are program examples implementing the "Matrix FFT" and

     "Matrix IFFT":

  MFFT     << ->ROW FFTLP ROW-> ->COL FFTLP COL-> >>

  MIFFT    << ->ROW IFFTLP ROW-> ->COL IFFTLP COL-> >>

  FFTLP    << -> n << 1 n START n ROLL FFT NEXT n >> >>

  IFFTLP   << -> n << 1 n START n ROLL IFFT NEXT n >> >>

  • Equation Writer/Equation Library interaction bug: If you pick an

     equation from the EQ library, enter solver for that equation,

     enter an algebraic on the stack like 'X^2', and press the down

     arrow key to view algebraic in EquationWriter, the name of the

     equation will appear in the EquationWriter along with the

     unassociated algebraic.

  Roms: M, P

  • BESTFIT: Occurs when a two dimensional array is stored in \GSDAT

     (SigmaDAT).  Pressing the BESTFIT softkey multiple times quickly

     can cause a warmstart, or SigmaDAT to be erased. This occurs

     sometimes just by pressing BESTFIT repeatedly, regardless of

     \GSDAT content.  This bug can also be triggered by pressing the

     BESTFIT softkey quickly after pressing any other key.  Simply

     pressing MODL then BESTKEY quickly will trigger the bug.

  Rom: P

  • PROOT: If you put a matrix of coefficients on the stack and

     press PROOT repeatedly, you will get a warmstart.

  Roms: A-R

  • MatrixWriter Bug: This shows up when deactivating and

     reactivating any of the two direction movement fields.  If you

     do this, the active matrix field won't move as it's supposed to.

     For example: Launch the matrix writer (check that your GOFORWARD

     field is activated).  Type [1] [ENTER]. The active matrix field

     moves forward as it should.  Deactivate the GOFORWARD field and

     activate it again.  Now enter [2] [ENTER] [3] [ENTER]. The

     digits should show up on the same row, but they don't, because

     after you deactivated and reactivated the GOFORWARD field, the

     active matrix field stops moving according to the movement

     fields.


What is new with the revision "J" ROM? (S/SX)

  3.5.  What is new with the revision "J" ROM? (S/SX)

  The revision J ROM has a faster equation writer, as well as some bug

  fixes.  Scrolling of graphics is also faster.

  One "problem" is that the revision J ROM changed some undocumented

  ROM entry points, which broke those programs that used them.  If you

  have a Rev J ROM, you will not be able to run some old programs.


What happened to ROM revisions G, H, I, O, and Q?

  3.6.  What happened to ROM revisions G, H, I, O, and Q?

  These versions either were never released to the public, or were

  skipped over.

  I have received confirmation of the existence of a HP48 S with ROM

  revision F.  So it appears revision F was in fact released to the

  public, although very few must have made before revision J came out.


Can I upgrade my HP48 S/SX?

  3.7.  Can I upgrade my HP48 S/SX?

  When the G/GX first came out, HP had a trade in program.  This is no

  longer in operation.  You can either try to sell you S/SX privately,

  or you can trade it in at EduCalc.  Contact them for exact trade-in

  details; their number is in Appendix E-5.


Can I upgrade my buggy GX to the latest ROM revision?

  3.8.  Can I upgrade my buggy GX to the latest ROM revision?

  As far as I know, not any more.  They had a program a in early '94,

  but it is over now.  Contact the following for more info:

       Hewlett-Packard Corporation

       Calculator Support

       1000 NE Circle Blvd

       Corvallis, OR 97330

       Phone: (541)-757-2004 option 1


What's the latest ROM version?

  3.9.  What's the latest ROM version?

  • Revision R is the latest ROM version of the G/GX series.

  • Revision J is the last ROM version of the S/SX series.


Why would I buy a S/SX rather than a G/GX?

  3.10.  Why would I buy a S/SX rather than a G/GX?

  Here's the top reasons to buy a S/SX instead of a G/GX (Thanks to all

  who contributed):

  1.   May be slightly cheaper, having only 32K RAM.

  2.   It isn't THAT outdated.

  3.   So what if it's a little slower?

  4.   You didn't need all those useless equations, graphics capabilities,

        and math and science functions anyways!

  5.   If you break it, you're out of less money!

  6.   You like seeing how much you can fit into 32K RAM.

  7.   You like slow file transfers, using Kermit instead of X-Modem.

  8.   You want to be able to use all those lists of SYSEVALs for the SX.

  9.   You like having only 3 ports available max.  33 is ridiculous!

  10. Since it doesn't have a built in equations library it is less

        likely to be banned on tests.

  11. Only wimps need GUI's, dialog boxes, and choose lists.


Questions about the Operating System and Using the HP

4. Questions about the Operating System and Using the HP

4.1   How do I find the checksum of an object?

4.2   I typed RULES on my G/GX and got a crossword puzzle!

4.3   Why does my HP48 occasionally "freeze" for a moment?

4.4   What do I do if my HP48 locks up?

4.5   My HP48 seems to take longer to turn on and off.

4.6   What are all the different ON-KEY combinations?

4.7   What are the different interactive self-tests?

4.8   I can't account for some of the RAM in the HP48!

4.9   What are the best methods for installing and removing libraries?

4.10 How can I attach large libraries?

4.11 Why does (1/3)*3 equal 0.999999999999?

4.12 Why does my HP say that 0 to the power of 0 equals 1?

4.13 What is RPN?

4.14 Why did HP use RPN in their calculators?

4.15 Is there an Alternative to Calculating in RPN?

4.16 Why do I get unexpected values when I add temperatures?

4.17 How can I add my own units? What's the 1_? unit for?

4.18 I want `pi' to be a numeric value, not a symbol.

4.19 What are those little numbers near the top of my screen?

4.20 What tricks are there for manipulating matrices?

4.21 Can I use my HP48 as a remote control?

4.22 Can the HP48 be used as a DTMF phone dialer?

4.23 How can I run a program on warmstarts and/or power-up?

4.24 I could speed up my HP-28S. How can I speed up my HP48?

4.25 Can I make my HP graph any faster?

4.26 How do I plot inequalities?

4.27 What is the hidden directory and how do I access it?

4.28 How can I recall one object from a memory archive?

4.29 How do I take the logarithm of a base other than 10 or e?

4.30 Are there any key combinations that aren't in the manual?

4.31 How do I find out about commands not in the GX manual?

4.32 How can one delete (or purge) an entire directory?

4.33 How does binary wordsize affect my calculations?


How do I find the checksum of an object?

  4.1.  How do I find the checksum of an object?

  Many documents (including this FAQ) make references to the "checksum"

  of an object.  This is a 16-bit user binary resulting from a CRC

  calculation on the contents of an object.  This binary is supposed to

  be relatively unique, with only 1 change in 65536 of accidental equal

  checksums on two different objects.  This allows you to distinguish

  programs that look the same but may be quite different (even if the

  size of them is the same).  It is also often used to verify correct

  transmission of files.

  You can find the checksum of an object using the BYTES command.

  This will return you two things - the size of the object in bytes on level

  1, and the checksum on level two.  Note that while the checksum of a

  variable name is the same as running the checksum on the object

  itself, the sizes will be differ by 4.5 bytes + the size of the

  variable name itself.

  In rare cases the checksum of two objects can be the same, even if the

  objects are different.  This is due to the limited nature of the

  HP48's checksum function.  You can use the SAME command in these

  cases.


I typed RULES on my G/GX and got a crossword puzzle!

  4.2.  I typed RULES on my G/GX and got a crossword puzzle!

  From: Joe Horn

  Many commercial programs (like Windows) have similar hidden screens

  that list the program's design team.  Since they are always so cute

  and well hidden, they are often referred to as "Easter eggs".  The

  RULES command on the G/GX is one such example.

  Try using the RULES command.  The names you see are as follows:


Easter Egg

ALCUIN was the HP-internal code name of the HP48 G

during development, because Alcuin was Charlemagne's

teacher, and Charlemagne, as you remember, was the

code name of the HP48 SX.

The other names in the "Easter egg" above belong to:

 • BILL Wickes (list processing; "Father of RPL")

 • CHARLIE Patton (RPL operating system)

 • TED Beers (parameterized outer loop; interactive stack;

    key handling system; high-level display management;

    input forms)

 • DIANA Byrne (project manager; plotting; graphics)

 • GABE Eisenstein (EquationWriter)

 • BOB Worsley (I/O)

 • PAUL McClellan (unit management; math)

 • CLAIN Anderson (product manager; marketing)

 • DENNIS York (manager)

 • JIM Donnelly (EQ LIB; list processing; variable

    tic logic; developer support)

 • MAX Jones (menu system; editing)

 • DAVE Arnett (hardware)

 • DAN Coffin (manuals)

 • RON Brooks (marketing)


Why does my HP48 occasionally "freeze" for a moment?

  4.3.  Why does my HP48 occasionally "freeze" for a moment?

  The HP48 must occasionally do "garbage collection" to free up unused

  memory, and it is this garbage collection that is causing the

  momentary "freeze".  "Garbage collection" is where the HP48 scans

  through memory, looking for objects that are no longer used.

  Using less stack supposedly makes garbage collection go faster.

  The easiest way to force a garbage collection is to run MEM DROP.

  Otherwise you can use #05F42h SYSEVAL or the SysRPL command GARBAGE.


What do I do if my HP48 locks up?

  4.4.  What do I do if my HP48 locks up?

  • NOTE: If you have it, read the sections in the GX manual starting

     on page 5-16, "Special Memory Operations", and "Testing Calculator

     Operation" on page A-9.

  • NOTE: under most circumstances, your calculator should never lock

     up.  Some earlier versions of the G/GX do this due to bugs.  Of

     course, depending on the program being run, it may appear to lock

     up, but pressing the "ON" key usually interrupts whatever the

     calculator is doing.  If it does lock up, this is usually caused by

     a buggy assembly-language or system RPL program, and, chances are,

     the memory contents of your HP48 are gone (as in "destroyed",

     "terminated", "wiped out", "deleted", etc.).

  1. First, check the batteries to make sure that they are installed

     correctly.

  2. Next, try is pressing the "ON" key again and again very RAPIDLY.

     The operative word here is "rapidly".  It's possible to write a

     program that can only be interrupted during a very narrow window,

     and so you must press the "OK" key again and again very rapidly to

     interrupt the program.  If the calculator doesn't respond within

     ten or so seconds, go on to the next step.

  3. Press "ON-+" a couple of times, just in case the LCD display

     intensity was turned down.

  4. If this doesn't work, the next thing to try is ON-C.  This is a

     "warm-start" or "system halt".   Note that this will CLEAR the

     stack.

  5. If this still does not work, it is possible that the HP is not

     responding because it is not accepting input from the keyboard.  It

     is possible to execute a system halt without the keyboard using the

     hidden reset button.  The reset button is hidden under one of the

     two upper rubber feet on the bottom of the calculator (it's under

     one of the two feet near the serial connector and I/R port).  Note

     that the location of the reset button (under which foot) varies

     from calculator to calculator.  If you gently pull out the rubber

     feet, you'll notice that there is a small hole under each foot.

     The reset button is located in the hole that has an "R" next to it.

     Once you've located the correct hole, you press the button by

     GENTLY sticking an unbent paper clip, into the hole with the "R"

     next to it.  Hold for one second and remove.

  6. The next thing to try is a complete memory reset.  Depending on the

     state of your calculator, this may or may not preserve the contents

     of memory.  At the very least, even if the contents are preserved,

     the contents of the HOME directory will probably be moved into a

     new directory below HOME (HOME will be empty with the exception of

     this new directory); you'll have to manually move the items back

     into HOME.  To perform a complete memory reset, press ON-A-F.

  7. If that fails, you should still be able to induce a complete memory

     reset by removing your batteries and pressing ON several dozen

     times.  This will drain the capacitor that stores information when

     the batteries are removed, and you should get a "Try to Recover

     Memory?" prompt if you have pressed ON enough times to reset your

     calculator.  You should definately try this method before even

     considering the next step!

  8. WARNING: the next method is HIGHLY unrecommended!  Permanent damage

     to your HP can result if you try this.  In particular, you could

     fry a couple diodes used to protect your HP48.  You have been

     warned!

     If your HP48 does not respond to any of the above attempts, you

     might consider reversing the polarity of 2 of the 3 batteries VERY

     BRIEFLY, pressing ON, then correcting the batteries.  Your HP48

     should start with a "Try to Recover Memory?" prompt.  Even

     reversing only 2 of the 3 batteries is dangerous, but it is safer

     than reversing all 3 batteries.

     Note that simply shorting the battery terminals will not discharge

     the storage capacitors.  There are diodes between the battery

     terminal and the storage capacitors which prevent the DC current

     from flowing backward.

     This method apparently drains the capacitors and reverse charges

     them by running current through the parasitic input protection

     diodes in the various CMOS chips.

  9. If all of the above fail, or if you decide not to try the last

     step, you may have to contact Hewlett Packard for service.


This means:

• Press and HOLD DOWN the "ON" key.

• Press and release the "+" key, WHILE HOLDING DOWN THE "ON" KEY.

• Release the "ON" key.


This means:

• Press and HOLD DOWN the "ON" key.

• Press and release the "C" key, WHILE HOLDING DOWN THE "ON" KEY.

• Release the "ON" key.


This means:

• Press and HOLD DOWN the "ON" key.

• Press and HOLD DOWN THE "A" key, WHILE HOLDING DOWN THE "ON" KEY.

• Press and HOLD DOWN THE "F" key, WHILE HOLDING DOWN THE "ON" AND

   "A" KEYS.

• Release all of the keys.

• At this point, the calculator will ask you if you want to recover

   memory.  Answer "yes" to this question.  Note that this can take a

   long time.  If you answer "no", all of memory will be cleared

   (the old contents will be lost).


My HP48 seems to take longer to turn on and off.

  4.5.  My HP48 seems to take longer to turn on and off.

  The usual causes for this are RAM/ROM cards and libraries.  When you

  turn the calculator on, it checks RAM (the more you have, the longer

  it takes), and checks to see if any libraries need initializing.

  Also, having a lot of alarms can supposedly also cause this.


What are all the different ON-KEY combinations?

  4.6.  What are all the different ON-KEY combinations?

  From: Dave Arnett

     ON In most cases, this will move you to, or toward, the stack

           environment.

     ON+A+F

          This is the manual Coldstart.  It will break out of almost any

          hung program, and offer you the dreaded option... "Try to

          recover memory?"  Note that this is your next-to-last resort in

          a lock-up, so don't give your machine this three-fingered salute

          unless you really want to possibly clear memory.

     ON+B

          This is the Oops! key for ON codes.  For many ON sequences, this

          cancels the operation, so long as you press the B before

          releasing the ON key.  Try it sometime, if you must, just so you

          remember it.  It can be a life-saver, in case of an accidental

          ON+A+F in process, or even accidentally hitting ON during a

          plotting routine.

     ON+C

          This will initiate a Warmstart.  You'll lose the stack and PICT,

          but it will often get you out of a locked up program with memory

          intact.

     ON+D

          Enters interactive test mode.  Back up your own machine and play

          around.  Exit this test mode with Warmstart, ON+C.  See the next

          question for all the various tests available here.

     ON+E

          Starts a looping self-test mode.  Kinda dull after the first

          five minutes, but it keeps a rather solid tempo.  Exit with

          Warmstart, ON+C.

     ON+4

          Cancels repeating alarms.

     ON+1

          Screen dump utility.

     ON+'+' and ON+'-'

          Adjusts display contrast.

     ON+SPC

          Initiates Coma Mode and clears Warm Start Log.  In Coma mode,

          all the clocked activity is halted.  The battery power drain is

          basically the few nano-amps nA necessary to sustain your RAM

          contents.  The Warm Start Log is a nearly bullet-proof area of

          memory which keeps track of the last four hazardous events.

          View it using the command WSLOG.  This log is one of the few

          things not cleared by a Coldstart.  But it is cleared by ON+SPC.

          Enter Coma this way if you want to clear the Warm Start Log, if

          you are planning to study crystal healing in Tibet for a few

          years and want to keep your pirated version of Tetris alive, or

          you just have a low power fetish.  Exit Coma mode with the ON

          key (tough to remember, huh?), and plan to find your stack

          cleared out.

          Two additional notes on this Coma stuff.  First, I'm not gonna

          try to list the log codes in WSLOG.  Sorry!  Second, if your

          machine is on, and you drop the batteries out, you will usually

          end up in a coma mode to preserve power.  WSLOG will not be

          cleared.  Instead, you will find a code 1 entry there.  Some

          people are paranoid and want to be in Coma when they change

          batteries, just in case they have a sudden emergency call from

          the Prime Minister and don't get back to their battery change

          for a half hour.  If you are one of these...  shall I say,

          weenies?  No, that would be unprofessional ...users, then I

          recommend you use the ON+SPC entry route, rather than the

          kamikaze method of dropping batteries with the machine running.

          Myself, I just turn the machine OFF, like the manual says.

          Now, a Coma story... sort of.  During the G/GX development, I

          maintained a small number of units on which I changed ROM chips

          as incremental code releases came out.  This was so folks like

          Bill Wickes and Jim Donnelly could have fully-real hardware to

          test, instead of just the EPROM handsets some of you may have

          seen.  We always backed up anything of importance in the machine

          before we did this.  But I got into the habit of using ON+SPC

          before I opened up the calculator.  Better than half of the

          time, I could remove the batteries, open the case, desolder the

          old surface-mounted ROM chip, solder down a new chip, and

          reassemble the machine... with all of RAM intact!  When I

          pressed ON, I'd come right back up without a "Try to Recover

          Memory?" prompt.  Pretty good, huh?  The folks who put that mode

          into the machine certainly weren't in a coma.


What are the different interactive self-tests?

  4.7.  What are the different interactive self-tests?

  Pressing ON-D enters the interactive self test function of the HP48.

  When you first press ON-D, your HP will beep and you will see 3

  vertical lines, one on each side of the screen and one in the middle.

  You can exit this mode with a Warmstart, ON-C.  The tests are:

     [A]	Displays CPU speed

     [B]	LCD test.  Press Enter to cycle through the tests

     [C]	Internal ROM test

     [D]	Internal RAM test

     [E]	Keyboard test.  Starting with [A], press all the keys in order,

        	left to right, top to bottom.  If all goes well, the HP will

        	show "KBD1 OK".

     [F]	Partial keyboard test

     [G]	ESD test monitor.  Battery status is shown by bars.

     [H]	UART loop-back test

     [I]	Wired UART echo

     [J]	Shows what cards are plugged in.  Press any key a few times.

     [K]	Test RAM cards in ports

     [L]	Blanks display

     [M]	Sends system time from IR port

     [N]	Receives system time from IR port (have another HP send it)

     [O]	IR loop-back test

     [P]	IR UART echo

     [S]	Shows test start time

     [T]	Shows test fail time

     [U] [V] [W] [X] [Y] [Z]

        	Looping test

     [ENTER]

        	Initialize test times

     [DEL]

        	Test summary

     [<-]	(Backspace) Enters memory scanner (SX only)

  When the HP48 is in test mode, the test results that are displayed

  on the screen are also sent to the serial port at 9600 baud, 8 bits,

  no parity, 1 stop bit.  This seems to be unaffected by any settings

  in IOPAR, PRTPAR, or the system flags.  I can only guess

  that this feature was included for factory testing purposes.  This

  does explain, however, why the I/O annunciator lights up so much

  during the self test.


ON-D or ON-E


I can't account for some of the RAM in the HP48!

  4.8.  I can't account for some of the RAM in the HP48!

  The HP48 S/SX/G have 32K base memory, and the GX has 128K.  However

  not all this memory is available to the user.  The operating systems

  uses memory for system variables, flags, fonts, last stacks, last

  arguments, last menus, and such.  It also can be any one of a number

  of things:

  1. Enabling the use of LAST STACK, LAST ARG, LAST CMD, etc., uses up

      extra RAM, as the calculator has to keep track of the last stack,

      arguments, command, etc..  This is particularly important with LAST

      STACK if you have a large/complex stack, as the HP48 has to keep

      enough information around to recreate the stack after each

      operation.  You can clear out these variables by pressing ON-C (but

      also note that this will clear out the stack, the graphics PICT,

      etc.)

  2. From William Wickes, a member of the HP48 development team: Here's

      a candidate for "most obscure way to use up memory on the HP48 SX."

      When a program executes DOERR with a string argument, the string

      and hence the program too if the string is embedded in the program

      are referenced for the sake of the ERRM command.  Thus if you purge

      the program, the memory used by the program is not reclaimed until

      the ERRM reference is updated to a new string.  If the string is in

      a port, you will get the Object In Use error if you try to purge

      the library or backup object containing the string.  A system halt

      prior to a PURGE will not help unless the object is in port 1 or

      port 2 (it will reclaim memory held by a successfully purged but

      still referenced object).  For port 0 objects, the only way to

      break the reference is to execute DOERR again with a new string.

  3. Occasionally, I have had problems with libraries disappearing, but

      still taking up memory.  I found that an "ON-A-F" reset will cause

      these libraries to re-appear. If you still cannot account for a

      large chunk of memory, I would suggest a hardware reset, after

      backing up your memory.


What are the best methods for installing and removing libraries?

  4.9.  What are the best methods for installing and removing libraries?

  To install a Library:

  1. Download it into a variable of the calc.

  2. Place the library on the stack.

  3. Type the number of the port in which you want to store the library

      in.  0 is appropriate if you do not have any expansion cards.

  4. Press STO to store the library in that port.

  5. Turn the calculator off and then on, or press ON-C, to finish

      installation of the library.

  Sometimes you have to purge the variable containing the library before

  storing it in a port, if you are low on memory.  See the next question

  for more information.

  If you have FXRECV installed: Just type a port number, hit FXRECV and

  the library will automatically go into the specified port.  All you

  have to do then in turn the calc off and then on to complete the

  installation.

  To delete a Library:

  Say you have library 1234 in port 0 that you want to delete.

  1. Go to the directory to which the library is attached.  In most

      cases this will be HOME.

  2. Enter :0: 1234

  3. Press [ENTER] or type DUP

  4. Type DETACH

  5. Type PURGE

  If this doesn't work, there may be a reference to the library still in

  temporary memory.  Try warmstarting with ON-C, then try again.


How can I attach large libraries?

  4.10.  How can I attach large libraries?

  If have just successfully transferred a library to your HP, and try to

  store it in a port you may get an "Insufficient Memory" error.  This

  is because your HP is trying to make a duplicate copy to store in your

  port, but it doesn't have any memory to do so.  This is especially

  true on the HP48 S/SX/G since they only have 32K of memory built in.

  The solution is to push the library into the stack, then purge the

  original variable containing the library.  At this point, the only

  copy of the library that exists is on the stack.  Now you can store

  the library in a port as usual.  This method avoids temporarily trying

  to have two identical copies in memory at the same time.

  For example, say you have a library in 'LIB' and you wish to store it

  in port 0.  You would enter the following:

  •  Go to the directory containing 'LIB'

  •  Recall the library to the stack: 'LIB' RCL

  •  Purge the original from user memory: 'LIB' PURGE

  •  Enter port number to store in: 0

  •  Press STO

  For the opposite problem - sending large libraries you can follow the

  reverse procedure.  That is, recall the object from the port to the

  stack, purge the original in the port, store it in a variable and then

  send it.

  Alternatively if the library is in a non-covered port (0/1/2 on SX or

  0/1 on GX) you can use the following simple program suggested by Dan

  Kirkland:

    \<< -> lib \<< 'lib' SEND \>> \>>

  This does not require a second copy of the library and avoids all the

  complications of trying to purge a library and then re-installing it.


Why does (1/3)*3 equal 0.999999999999?

  4.11.  Why does (1/3)*3 equal 0.999999999999?

  This is due to the way numbers are typically represented by computers

  and calculators.  There are infinitely many numbers, like `1/3' and

  `pi', that cannot be exactly represented internally (their decimal

  representations go on forever, and often cannot even be represented as

  a fraction, as in the example of `pi').  As a result, any calculations

  that use these numbers are bound to be off.


Why does my HP say that 0 to the power of 0 equals 1?

  4.12.  Why does my HP say that 0 to the power of 0 equals 1?

  Some claim that 0^0 is defined as 1, some claim it is indeterminate.

  The HP mathematicians decided to use the definition.  Here is some

  more concrete info shamelessly lifted from the Sci.Math-FAQ:

     Question:

        What is 0^0 ?

     Answer:

        According to some Calculus textbooks, 0^0 is an "indeterminate

        form". When evaluating a limit of the form 0^0, then you need to

        know that limits of that form are called "indeterminate forms",

        and that you need to use a special technique such as L'Hopital's

        rule to evaluate them. Otherwise, 0^0=1 seems to be the most

        useful choice for 0^0. This convention allows us to extend

        definitions in different areas of mathematics that otherwise

        would require treating 0 as a special case. Notice that 0^0 is a

        discontinuity of the function x^y.

        Rotando & Korn show that if f and g are real functions that

        vanish at the origin and are analytic at 0 (infinitely

        differentiable is not sufficient), then f(x)^g(x) approaches 1

        as x approaches 0 from the right.

        From Concrete Mathematics p.162:

        "Some textbooks leave the quantity 0^0 undefined, because the

        functions x^0 and 0^x have different limiting values when x

        decreases to 0.  But this is a mistake.  We must define:

        x^0 = 1 for all x,

        If the binomial theorem is to be valid when x=0, y=0, and/or

        x=-y.  The theorem is too important to be arbitrarily

        restricted! By contrast, the function 0^x is quite unimportant."

        Published by Addison-Wesley, 2nd printing Dec, 1988.

     References:

        H. E. Vaughan, The expression '0^0', Mathematics Teacher 63

        (1970), pp.111-112.

        Louis M. Rotando & Henry Korn, "The Indeterminate Form 0^0",

        Mathematics Magazine, Vol. 50, No. 1 (January 1977), pp. 41-42.

        L.J. Paige, A note on indeterminate forms, American Mathematical

        Monthly, 61 (1954), 189-190; reprinted in the Mathematical

        Association of America's 1969 volume, Selected Papers on

        Calculus, pp. 210-211.


R. Graham, D. Knuth, O.Patashnik


What is RPN?

  4.13.  What is RPN?

  Jan Lukasiewicz wrote a book on formal logic in 1951 that showed that

  mathematical expressions could be specified without parentheses by

  placing the operators before (Polish Notation) or after (Reverse

  Polish Notation) the operands.  For example, the expression:

       (4 + 5) * 6

  Could be expressed in RPN as:

       4 5 + 6 *

       6 4 5 + *

  Polish Notation is also known as prefix notation and Reverse Polish

  Notation (RPN) is also known as postfix notation.


Why did HP use RPN in their calculators?

  4.14.  Why did HP use RPN in their calculators?

  In the years that followed Lukasiewicz's book, computer scientists

  realized that RPN or postfix notation was very efficient for computer

  math.  As a postfix expression is scanned from left to right, operands

  are simply placed into a last-in, first-out (LIFO) stack and operators

  may be immediately applied to the operands at the bottom of the stack.

  By contrast, expressions with parentheses and precedence (infix

  notation) require that operators be delayed until some later point.

  Thus, the compilers on on almost all modern computers converted

  statements to RPN for execution. (In fact, some computer manufacturers

  designed their computers around postfix notation.)

  At the time that the HP-35 was introduced, other pocket calculators

  typically used a partial algebraic model.  That meant they could

  evaluate trivial expressions like 4+5 but couldn't handle anything

  that involved parentheses or algebraic precedence.  The technology of

  the time didn't allow for full algebraic compilers in pocket

  calculators.

  RPN allowed HP to produce a pocket calculator that could evaluate

  arbitrary expressions using the available technology.  For many,

  learning a new style of entry was a small price to pay to be able to

  evaluate arbitrary expressions on a calculator.  Once the technology

  to produce algebraic compilers could fit into a pocket calculator,

  most RPN users had decided that RPN was more efficient and consistent

  for the user as well as for the calculator.  Also, because

  subexpressions are evaluated as they are entered, entry errors are

  more obvious with RPN.

  Another advantage to RPN is consistency between machines.  Early

  algebraic models had differing limits of the complexity of the

  expressions they could evaluate.  For example, TI catalogs from the

  late 70's listed how many levels of parentheses and pending operations

  each model could handle.  Even today if you begin to use an algebraic

  calculator, you need to determine just "how algebraic" it really is.

  For example, some switch to RPN for unary operators (ie 5 SIN rather

  than SIN(5)) and some can't directly enter an expression like:

        4+5

       --------

        6+7


Is there an Alternative to Calculating in RPN?

  4.15.  Is there an Alternative to Calculating in RPN?

  Many people just can't get used to the interaction with the stack to

  do calculations.  A simple alternative is to place your equation in

  tic marks like '8+10*3' and to use the EVAL as an equals key.  This

  way you can enter numbers just as you would write them on paper.


Why do I get unexpected values when I add temperatures?

  4.16.  Why do I get unexpected values when I add temperatures?

  Example:

  I add two temperatures like 34 deg.F and 11 deg.F, and I get

  504.67 deg.F.  Why don't I get 45 deg.F?

  This occurs with the S/SX only.  This behaviour changed in the G/GX.

  With the G/GX, adding 34 deg.F and 11 deg.F will give 45 deg.F using

  TINC and TDELTA.  However, the G/GX will only add or subtract

  temperatures if the units are the same; it is now an error if they are

  not.

  If the units attached to the number consists only of a temperature and

  nothing else, operations are done using an absolute temperature scale

  (relative to absolute zero).  If the units consists of a temperature

  and something else, such as degrees/minute, the operation will not be

  done using an absolute temperature scale.

  It also does not make any physical sense to add two temperatures.

  You can't add a cup of water at 20 degrees C to a cup of water at 30

  degrees C and end up with two cups of water at 50 degrees C.


How can I add my own units?  What's the 1_? unit for?

  4.17.  How can I add my own units?  What's the 1_? unit for?

  Note: Some later editions of the G/GX series manuals have some similar

           information on this subject.

  Another feature is the generic unit, 1_?.  It seems to be intended as

  a generic unit, to allow you to make new units not based upon any of

  the built-in ones.  You could use it to create a conversion utility

  for currencies or bits and bytes.  Before you create either, check the

  FTP sites to see what others have done in this regard.

  • User units may be defined by creating a variable of any name.

     into which you store its definition in terms of other units,

     e.g. 2_mph 'stroll' STO; you can also use other user

     units in a definition, e.g. 3_stroll 'run' STO.

  • You can then use the new unit name(s) in any custom or temporary

     menu, just the same as any other unit in the built-in Units

     Catalog.  For example, { 1_stroll 1_run ... } TMENU

       Here's an example. Convert this using ASC\\-> and save it as 'sample'.

   "69A20FF78E000000005046F6E6574750ADA209C2A2C2A2070000F368B01B2130

   E20005046F6A756E650ADA20339201000000000000210C2A20F000046F6E6574

   768B01B2130640005086F6D6562750ADA20339200000000000000510C2A20F00

   0046F6E65747C2A20B0000D696E686B0168B01B2130B5000303435453047A204

   7A20C2A20F000046F6E65747ADA209C2A2C2A20F000046F6E6574768B01B2130

   B213047A20C2A20F000046F6A756E6ADA209C2A2C2A20F000046F6A756E668B0

   1B2130B213047A20C2A20F000086F6D65627ADA209C2A2C2A20F000086F6D656

   2768B01B2130B2130B2130F0DA"

  This is a sample directory with a custom menu.  Enter the directory

  and press the CST key.  Here you will see three units (truncated to

  fit the softkeys): donut, dozen, and homer. A dozen is defined as

  12_donut, and a homer is a rate of 1.5_donut/min (not part of the SI

  system).  These units may take SI prefixes described on page 10-5 of

  the User's Guide, so you may convert the value of 3_MW*h/kdonut into

  units of erg/mdozen using CONVERT, for example.  The items in the CST

  menu have the usual abilities of unit menu objects as described on

  pages 10-2 and 10-3 of the User's Guide.  These units can be used for

  math operations described on page 10-7 of the User's Guide, such as

  adding 2_donut to 1_dozen.

  Example:

  At your power plant, you have four control room operators who

  have a combined consumption rate of 2.28 homers.  How many donuts will

  they use in 5 minutes and 17 seconds?

  • Enter the rate.

  	2.28 homer

  • Enter the time.

Right-shift UNITS [TIME]

5 [min]

17 [s]

  • Multiply the time by the rate (*)

  • Convert to dozens:

  CST Left-shift dozen

  • The answer is a little over 1.5 dozen.


the new unit name


I want `pi' to be a numeric value, not a symbol.

  4.18.  I want ´pi' to be a numeric value, not a symbol.

  You are using "Numeric Constants Mode".  To turn this mode on or off:

     SX:

        Type -2 SF.  This turns the numeric constants mode on.  To turn

        it off, type -2 CF.

     GX:

        Go to the MODES menu.  Hit the key for FLAG submenu.

        Toggle the second flag "Constant -> symb" to turn on and off.


     press green/right-shift MODES


What are those little numbers near the top of my screen?

  4.19.  What are those little numbers near the top of my screen?

  The little numbers are "user flags".  When you or a program sets any

  of the user flags 1 through 5, little numbers corresponding to the set

  flags are displayed at the top of the screen.

  The HP uses negative flags for setting various modes and functions,

  while positive flags were reserved for the use of the user.  To set a

  user flag type the number, then SF.  To clear a user flag type the

  number, then CF.

  Some programs will use the user flags without you being aware of it.

  So, if you have a "1" at the top of the screen you can type 1 CF to

  get rid of it.


What tricks are there for manipulating matrices?

  4.20.  What tricks are there for manipulating matrices?

  SX:

     You can build up a matrix by rows using \GS+.  You can take a

     matrix apart by rows using \GS- These two commands add and

     subtract rows from the SigmaDAT Statistics matrix.

     \GS+ takes a vector row and adds it to SigmaDAT, and

     \GS- takes the bottom row away from SigmaDAT.  \GS+ is

     accessible from the STAT menu with its own softkey.  \GS- can be

     obtained by pressing left-shift /GS+, or by typing it in at the

     command line.

  GX:

     The GX has many matrix functions built in.  See Appendix B-1.


       \GS is Sigma (Greek E)


Can I use my HP48 as a remote control?

  4.21.  Can I use my HP48 as a remote control?

  There are numerous programs available for using your HP48's IR port as

  a remote control.  However, the level of support depends on the

  particular unit you wish to control.  The HP48 is capable of reproducing

  many of the IR controls of many popular brands of appliances.

  However, some remotes run at speeds that the HP48 is unable to

  reproduce.  Due to their faster processor speed, the G/GX calculators

  are able to support more remote controls but are still limited in some

  cases.

  With typical remote programs you have to "teach" your HP48 by sending

  it the various IR sequences with the original remote control.  There

  are some advantages to using your HP48 however:

  •  You can impress your friends that you can use your calculator to

      control your TV!

  •  You can set alarms to turn your things on and off at predetermined

      times.

  •  You can use it as a universal remote.

  The best remote program by far is Remote by Bjorn Gahm.  It has a

  large database of existing remotes, meaning you may not have to

  "teach" your HP48 your specific remote if it is already supported.

  However it also have the ability to learn new codes.  See the best

  programs list for the specific URL.


Can the HP48 be used as a DTMF phone dialer?

  4.22.  Can the HP48 be used as a DTMF phone dialer?

  To make phone dialing tones, you need to produce two simultaneous

  tones.  The tones used to dial phones are known as DTMF tones,

  which consist of two tones at the same time.

  The speaker in the HP48 is not capable of supporting the DTMF tones

  because it can only make a single tone at a time.  The best the HP48

  can do is switch very quickly between one frequency and another.  Some

  attempts have been made in machine language to support DTMF, however

  they have been unsuccessful.  Therefore, you cannot use the HP48 as a

  phone dialer.


      dual tone multi frequency


How can I run a program on warmstarts and/or power-up?

  4.23.  How can I run a program on warmstarts and/or power-up?

  You can use some of the utilities available on the Educalc Goodies

  Disks (see Appendix E.5 on where to obtain these):

  •  AUTOBOOT (GD #7) warmstarts every power-up

  •  AUTOEXEC (GD #10) Runs 'GO' every power-up

  •  AUTOPORT (GD #7) Runs &:AUTOEXEC every warmstart

  •  AUTOSTRT (GD #7) Runs AUTOEXEC every warmstart

  Some stack libraries come with support for AUTOEXEC or an equivalent

  built in (for example, the Java library supports AUTOEXEC).  If one of

  the libraries you have installed supports such a feature, you may not

  need any of the utilities above.


I could speed up my HP-28S.

  4.24.  I could speed up my HP-28S.  How can I speed up my HP48?

  You can't, really.  Unlike the HP-28S, the clock speed in the HP48 SX

  is hardwired to 2 MHz, and to 4MHz in the HP48 GX.

  However, in some cases, you can speed up the HP48 by turning off the

  display refresh, which supposedly takes up about 11% of the CPU time.

  Detlef Mueller submitted a program called SPEED to comp.sources.hp48

  that turns off the display refresh.  Of course, since it turns the

  display off, it is only suitable for long non-interactive runs like

  calculating large integrals, compiling, etc...  Look in the various

  HP48 archives for a copy.


Can I make my HP graph any faster?

  4.25.  Can I make my HP graph any faster?

  Try lowering the plotting resolution by typing #2 RES.  You can use

  larger values for faster speed at the expense of number of points

  plotted.  In the GX Plotting Options Menu this setting is known as the

  "STEP" rate.


How do I plot inequalities?

  4.26.  How do I plot inequalities?

  In the user's manual, inequalities are referred to as "truth plots".

  They are defined as expressions that return true (any nonzero real

  number) or false (0) results.  In a truth plot, a pixel is turned on

  if the expression is true, it's unchanged if the expression is false.

  For example to plot the simple inequality 'X>0' you could do:

    TRUTH

    -20 20 XRNG

    -10 10 XRNG

    ERASE DRAX DRAW

  For more complicated examples see your manual, or on a G/GX you can

  type TEACH to look at some of the built-in examples.  It may also be

  useful to plot the lines defining the outline true region.  This is easily done

  by changing the plotting style to FUNCTION or CONIC and plotting again,

  taking care not to erase any previous plot.

  Note that unless otherwise specified, every pixel in the display must

  be evaluated.  As such, truth plots can be very slow.  If you have a

  general idea on which values are going to return true, you can speed

  up plotting by specifying a smaller x and y plotting range.  You can

  do this by setting the "LO" and "HI" input forms on a G/GX, which can

  be different than the actual display range.

  If you are plotting the area between two equations, you speed up

  plotting dramatically by avoiding a TRUTH plot entirely.  Store the

  two equations as the first two items in the current EQ list.  Using

  NXEQ in the FCN menu will rotate the list as desired to plot both

  functions.  Then the area between them can filled in very quickly

  using the SHADE key of the FCN menu (in the PICTURE environment).

  Another hint for speeding up Truth plots is to set the resolution, say

  to 2 pixels or more, which also results in a different "shading

  pattern".  The resolution can be set with the RES command.


What is the hidden directory and how do I access it?

  4.27.  What is the hidden directory and how do I access it?

  The "hidden directory" is a subdirectory of the HOME directory.  It is

  created on startup, and it contains variables with your alarms and

  user key configurations.  You can use the hidden directory to store

  whatever you want, however you CAN NOT ORDER the contents of this

  directory, as this causes memory loss.

  The name of the hidden directory is a null character, ''.  The only

  way to get a null character is to use a syseval.  You can use the

  following program to access the hidden directory:

  <<  HOME	 (changes to home dir)

           #15777h	 (syseval to get null character)

           SYSEVAL	 (returns '' to stack)

           EVAL >>	 (changes to hidden dir)

  To exit the hidden directory, use HOME or UPDIR.  This will return you

  to the HOME directory.

  Also, by putting the null character as a part of your HOME custom

  directory, you can switch right into the directory by pressing the

  softkey.

  Note: The SysRPL command NULLID returns a null character to the stack;

            it is the same as doing #15777h SYSEVAL.


How can I recall one object from a memory archive?

  4.28.  How can I recall one object from a memory archive?

  From: Joe Horn

  There is a little-known method of recalling objects from within

  archives.  Just make a list representing the PATH to the object, and

  tag the list with the port number.  Then hit RCL or EVAL.

  For example, if your archive in port 1 is called BKUP, and it contains

  a directory called GAMES which contains a program called REVERSI, you

  can run the game directly (without having a separate copy of REVERSI

  stored anywhere!) by:

       :1: { BKUP GAMES REVERSI } EVAL

  Or, you can RCL instead of EVAL, and it will be pushed onto the stack.

  • This method only works in ports 0 and 1 in a GX.  It works on any

     port in the SX.

  • This method works with directory objects stored as backup objects,

     as well as with the results of the ARCHIVE command, because they

     are both really the same thing.


How do I take the logarithm of a base other than 10 or e?

  4.29.  How do I take the logarithm of a base other than 10 or e?

  To take the log of a number other than base 10 or e, say log x base y,

  you use the formula:

         ln x

       --------    where ln is natural log (log works too)

         ln y

  A quick program to do it would be: << SWAP LN SWAP LN / >>

  With the input of:

       2: x

       1: y


Are there any key combinations that aren't in the manual?

  4.30.  Are there any key combinations that aren't in the manual?

  From: John Meyers

  Yes, on the G/GX there are a few keys that aren't mentionned.

  They are:

  •  right-shift down-arrow = Review menu keys

  •  right-shift right-arrow = Kermit server mode

  Right-shift View is hidden in Appendix G (Operation Index) of the

  User's Guide Edition 4 (which comes with the calc), among the several

  entries for the word VIEW.

  AUR Edition 1 (in chapter 3, Command Reference, under SERVER) gives

  the alternate keys right-shift cursor right (but of course AUR doesn't

  come with the calc).  This alternative was left out of Appendix G of

  the User's Guide.  Donnelly's HP48 Handbook 2nd Ed. even lists it

  first!


How do I find out about commands not in the GX manual?

  4.31.  How do I find out about commands not in the GX manual?

  From: John Meyers

  Besides purchasing the Advanced User's Reference Manual (AUR), you can

  look in Appendix G of the G/GX User's Guide, which briefly summarizes

  every command available in the G/GX, including all the commands not

  mentioned anywhere else in the User's Guide.  Often even the brief

  description given in this Appendix is sufficient for you to use the

  command (and to know it exists!).

  Some notes on omissions, however:

  •  VERSION and "_" (attach unit) are missing in Edition 4.

  •  SUB works with arrays in the G/GX, but this is not in the HP

      manuals, nor in Donnelly's HP48 Handbook 2nd Ed 6/93.  You can

      specify any two "corners" of a rectangular sub-matrix (like with

      GET), and it extracts the sub-matrix.  Also works with vectors.


How can one delete (or purge) an entire directory?

  4.32.  How can one delete (or purge) an entire directory?

  •  To purge a subdirectory and all that it contains, type in the name

      in single quotes, then PGDIR.

  •  To purge all variables in the current directory, but not the

      directory itself, type CLVAR.

  Note that with CLVAR, if the current directory contains a non-empty

  subdirectory, an error occurs at that point, and no subsequent

  variables are purged.


How does binary wordsize affect my calculations?

4.33.  How does binary wordsize affect my calculations?

  From: John Meyers

  Some of the following (but not all) is in the User's Guide, under

  "Binary Arithmetic and Number Bases" (Chapter 15 of G/GX).

  The system flags contain a segment which specifies a "binary word

  size".  This word size limits how many low-order bits of a binary

  value are displayed on the stack, and equally determines how many

  low-order bits of the arguments and results of binary

  arithmetic/logical/shift operations are used.

  Curiously, the binary word size has no effect on entering values into

  the command line - what you originally enter is displayed in truncated

  form on the stack, but when you view it again in the command line

  (which temporarily reverts back to STD numeric display and 64-bit

  wordsize) you will find the complete value as entered is still intact.

  As soon as you begin using functions on that value, however, the

  arguments to binary functions get truncated to the current wordsize

  before the functions are executed, and then the final result of the

  function gets truncated again.

  You can recall the current wordsize using RCWS and set the wordsize

  using STWS.  STWS accepts a real number argument in the range 1-64

  (out of range values get adjusted to either 1 or 64), and it also

  accepts a binary argument, in which case the absolute value of the

  low-order 20 bits is used (just in case you wondered why #1048576d

  STWS RCWS gives an answer of 1).

  Don't try adjusting the binary wordsize in the hope of saving memory

  by using shorter values; every "user binary integer" (type 10)

  produced by User RPL occupies 13 bytes, no matter what the current

  wordsize; the HP48 just sets the leading bits to zero when displaying

  on the stack or performing calculations.


Cards,data transfers,batteries,hardware

5. Questions about cards, data transfers, batteries, and hardware

5.1   My HP48 seems to making a high pitched noise.

5.2   Can I upgrade my S or G to more than 32K ram?

5.3   Can I add a lithium battery backup?

5.4   How can I get/build a cable for my HP48?

5.5   HP seems to offer two link kits with different prices.

5.6   Is there any communications software available?

5.7   Why doesn't the I/R port work farther than a few inches?

5.8   Can my HP48 talk to my HP100LX via Infrared?

5.9   Can I print to a LaserJet printer with an HP48?

5.10  I downloaded a program but all I get is "HPHP48-..."!

5.11  What is the structure of HP48 ASCII headers?

5.12  Why do Kermit transfers seem to get slower?

5.13  Why does XRECV not work sometimes? (GX)

5.14  What do the funny symbols in this document mean?

5.15  What are the pinouts for the HP48 serial connector?

5.16  Is there any information on interfacing to the HP48?

5.17  How can I transfer programs/data from my HP-28S to my HP48?

5.18  Can I use rechargeable batteries with the HP48?

5.19  How can I tell, from within a program, if the battery is low?

5.20  I lost the information on my RAM Card when I changed the battery!

5.21  Why do I get an "Invalid card data" error when I merge a RAM card?

5.22  I've heard about other manufacturer's RAM cards. Will they work?

5.23  How does RAM card locking work?

5.24  Why does the HP48 SX display flicker slightly?

5.25  I broke the LCD screen is there an easy way to get another?

5.26  How can I protect my LCD?

5.27  Is there a rigid (protective) case for the HP48?

5.28  Can I use my Amateur Radio with my HP48?


My HP48 seems to making a high pitched noise

  5.1.  My HP48 seems to making a high pitched noise.

  From: Dave Arnett

  High-pitched noise from HP48's is normal and harmless, and has been

  attributed to the internal power supply.

  The guts of the HP48 keyboard are assembled from several layers of

  mylar and similar material.  Some of the layers have conductive ink to

  create switch contacts.  Some are insulators, with appropriately

  located holes through which the switch contacts meet.  Some are

  embossed with spherically domed areas, to provide the snap-spring feel

  when you press the plastic keys.  The entire multi-layer sandwich is

  assembled onto plastic pegs on the backside of the HP48 top case,

  along with the metal chassis, and then the pegs are "heat stacked",

  positively capturing and holding the matrix together.

  These parallel planes can act like a capacitive speaker.  Most

  loudspeakers in home electronics are inductive: a sheet or cone moves

  because current passes through an attached coil positioned in a

  magnetic field.  A capacitive speaker creates sound by moving a sheet

  or diaphragm due to electric charge forces, whether attracting or

  repelling.  The HP48 keyboard has the necessary characteristics to be

  a very inefficient (therefore quiet) capacitive speaker.

  When the HP48 "scans" the keyboard, charges are placed on the parallel

  sheets of mylar.  They tend to move as a result of the charge, and

  create a faint squeal or whine.  The loudness will depend on a number

  of factors, and can vary significantly from HP48 to HP48.  Some folks

  report that, on their HP48, the sound is stronger on the back than on

  the front; others report the opposite.


Can I upgrade my S or G to more than 32K ram?

  5.2.  Can I upgrade my S or G to more than 32K ram?

  It is possible to do this by opening up the case and adding some

  memory chips.  There is a zip file containing instructions and

  schematics available for FTP:

  <ftp://ftp.cis.com/pub/hp48g/uploads/48gs256k.zip>

  There is a web page on how to open your HP48 from the back at

  <http://www.contrib.andrew.cmu.edu/~drury/how2open.htm>

  This is an illustrated guide on how to open your HP48 from the back.

  It has full instructions, as well as 15 pictures of the calculator in

  various stages of disassembly.

  An alternate way to open your HP48 and upgrade it to 256K is described

  at the following site, along with lots of pictures:

  <http://diwww.epfl.ch/~sgrundsc/upgrade.html>

  WARNING:	It is possible to ruin your HP in the process of performing

any one of these upgrades.  Do not even attempt it unless

you are adept at working with small electronics.  The FAQ

maintainer and the authors of the instructions take no responsibility

for anything you do to your HP!


Can I add a lithium battery backup?

  5.3.  Can I add a lithium battery backup?

  From: Lee Studley <RStud39515@aol.com>

  I recently did a modification to my 48G by replacing the 32K ram with

  a surface mount 128x8 RAM.  Afterwards, I sandwiched 2nd and 3rd RAM

  chips by stacking them up and soldering.  The 2nd CS was jumpered over

  to the expansion pin 21a.  The decode for the 3rd part was easy to

  figure out.  I've also added a lithium battery to insure memory

  retention.  This thing now has 128K user memory, 128K in port 1, and

  128K in port 2.  Additional port 2 chips can easily be added.

  The 3 volt lithium battery used was the generic coin type. I just made

  room for the holder and battery by removing the aluminum shield up to

  the plastic post near the piezo element.  The positive terminal of the

  battery goes through a 470 ohm resistor into the anode of a schotky

  diode (only 0.2 volt forward drop).  The cathode end of the diode

  feeds the positive side of the big 1000 uF capacitor near the added

  74HC00.  This is the memory retention cap when the batteries are

  removed.

  This way, the lithium battery only gets used if the main batteries are

  removed or very low.  Seems to work well so far.  The ground

  connection broken by cutting the aluminum shield kills the reset and

  piezo contact points.  To fix this, I stretched the original piezo

  contact spring and cut it in half.  Then I soldered the cut piece to

  the ground "twisted" tab near the original spring.  (readers should

  verify this ground with a meter.)  This restored the lost functions.


How can I get/build a cable for my HP48?

  5.4.  How can I get / build a cable for my HP48?

  Some places that sell the HP48 also sell the cable required for

  interfacing with a PC.  Unfortunately, most don't.

  For information on how to build your own cable, see Appendix D-1.

  If you want to buy one, there are a few options.  Places like Educalc

  and ElekTek sell them for around $20-$25.

  There are a few netters that make cables for sale also.  Contact:

  •  Chris Edmunds <chris@muffet.com>

      Web page: <http://muffet.com/hp/cables/ad.html>

  •  Joel Kolstad <kolstadj@peak.org>

  •  Ofer Asif <oasif@herbie.unl.edu>

  If you live in a larger city, you can look in the Yellow Pages for a

  listing of HP authorized dealers who either have the cables in stock

  or can order them in about the same time a mail order place can, but

  for a lower price.


HP seems to offer two link kits with different prices.

  5.5.  HP seems to offer two link kits with different prices.

  HP offers two link kits, one which sells for about US$20, and the

  other which sells for about US$50.  The only difference between the

  two is the higher priced kit comes with software and a manual.  The

  cable, however, is the same in both kits.

  As mentionned in the next question, free alternatives to this software

  are readily available.  HP's software also includes some assorted

  miscellaneous programs and games, all of which are also available from

  HP via FTP or WWW.


Is there any communications software available?

  5.6.  Is there any communications software available?

  In Windows 3.x you can use Terminal (in Accessories).  In Windows 95

  and OS/2 Warp, HyperTerminal can be used, or you can use any other

  "terminal emulator" package with some level of embedded Kermit file

  transfer capability.

  However, the most complete functionality is available with full

  Kermit, which can be downloaded from  <ftp://kermit.columbia.edu/>

  or HP.  Columbia University is the original site for Kermit and has

  versions for nearly all operating systems, including all forms of

  Unix, Amiga, and Macintosh.

  Of course if you have a G/GX machine you can use X-Modem instead of

  Kermit (X-Modem is generally faster).  [Hyper]Terminal works fine for

  X-Modem as well.  Alternative file transfer software is available from

  the FTP sites mentionned in the Appendix, or can be purchased

  (e.g. Donnelly's HP48 File Manager).


Why doesn't the I/R port work farther than a few inches?

  5.7.  Why doesn't the I/R port work farther than a few inches?

  It turns out that it is the receiver that is "crippled".  The transmit

  range is somewhere around several feet, and some people have actually

  written programs to make the HP48 emulate some remote controls (see

  Appendix E-1 for suggested programs).

  There are currently two stories going around as to why.  I will

  present both of them in the interest showing all sides of the story.

  You are free to decide which you believe:

  1. The head of the HP48 design team, Dr. William Wickes himself,

     alluded during the Chicago Handheld Conference that the IR was

     intentionally crippled due to the concerns of certain individuals

     in academia that students could literally 'beam' information from

     one 48 to another during examinations. (from Rick Grevelle)

  2. The reason the IR reception distance is so short is battery

     capacity.  The Infrared Transmitter is semaphore: It is only turned

     on when it needs to be on, and the transmission protocol is defined

     to minimize the ON time.  The receiver, by contrast, must be on

     continually when a transmission is in process, or when a

     transmission is expected. If you set your HP48 to Server mode, that

     receiver is drawing power. If you tweak the control bits to

     activate the receiver for any other reason, it is drawing power.

     The instantaneous peak power drawn by the transmitter is much

     higher than that of the receiver.  But in the long run, the

     receiver will draw more energy from the batteries.  Increasing the

     receiver sensitivity costs even more power.


Can my HP48 talk to my HP100LX via Infrared?

  5.8.  Can my HP48 talk to my HP100LX via Infrared?

  Yes, it can, although slowly.  Set the HP100LX at 2400 baud, and put

  it in server mode (under the Kermit Commands menu).  Then you can send

  stuff from your HP48 to your HP100LX.


Can I print to a LaserJet printer with an HP48?

  5.9.  Can I print to a LaserJet printer with an HP48?

  From: Derrik Pates

  Yes you can, but you need the HP PCL library from hpcvbbs.cv.hp.com.

  It allows you to communicate with any printer that supports PCL (all

  HP DeskJets and LaserJets, as well as some other laser printers and

  inkjet printers).  You can hot-switch your resolution and turn PCL

  on/off with software commands.

  The URL for the PCL extension page is:

  http://hpcvbbs.external.hp.com:80/software_archives/calc/

  System_Extensions/pclprint.html

  Although newer HP printers such as the 5P and 5MP have an IR port, you

  cannot use it to print directly from your HP48.


I downloaded a program but all I get is "HPHP48-..."!

  5.10.  I downloaded a program but all I get is "HPHP48-..."!

  Some versions of Kermit distinguish between ASCII and binary files,

  and so you have to worry about the transfer modes at both ends of the

  connection (the HP48 SX end and the computer end).  For example, when

  receiving ASCII files, Unix Kermit must translate CR/LF pairs into LF.

  If the HP48 SX is transmitting a binary file, but the Unix Kermit is

  expecting ASCII, any CR/LF pairs in the binary file will get

  translated to LF, corrupting the binary file.  Unfortunately, you

  cannot "uncorrupt" the corrupted binary file by simply reversing the

  transfer and expecting Kermit to translate LF to CR/LF.  This is

  because the binary file may contain occurrences of LF that were not

  originally part of a CR/LF sequence.

  When a binary file gets corrupted, it will display on the stack as a

  string, starting with the characters "HPHP48-", and continuing on with

  a bunch of garbage.  Thanks to two programs, these strings can be

  reconverted to binary files right on the HP48.  These programs are:

  FIXIT, by Joe Horn and Mika Heiskanen, or OBJFIX, written by our

  friends at HP.  These are included in Appendix A-2.

  The major difference between FIXIT and OBJFIX is the way they operate.

  I have never personally had any problems with either.  FIXIT takes the

  bad "HPHP48-" string from level 1 of the stack, and replaces it with

  the correct binary object.  OBJFIX takes the name of the variable in

  which the "HPHP48-" string is stored from level 1 of the stack, and

  puts the correct binary object directly in the variable where the bad

  string was stored.  It's up to you which you prefer.  I would suggest

  reading the documentation of both before using either of them.

  There is also a quick fix available from Dan Kirkland:

  Here is a simple SYSEVAL program that will return a pointer to the

  object in those data transfer strings that start with "HPHP48-"

  Checksum: # 8FEh

       << "12" SWAP + # 402Bh SYSEVAL # 62B9Ch SYSEVAL >>

  That's all!  (Simple huh!)  Name?  Whatever you want!!  Works on all

  48s (S/SX, G/GX)


What is the structure of HP48 ASCII headers?

  5.11.  What is the structure of HP48 ASCII headers?

  From: Jorge Costa

  ASCII file headers such as %HPHP: T(3)A(D)F(.); are created by the

  HP48 when an ASCII file is sent to the PC and read when a HP48 ASCII

  file is received from the PC.  They serve to preserve various settings

  on your HP that affect ASCII transfers.  They do not affect binary

  mode transfers.

  Three parameters are saved:	(T)ranslation Mechanism,

(A)ngle Mode,

  	(F)raction Mark

     Translation Mechanism:

        The possible ASCII translation schemes are as follows:

T	HP48 -> PC	PC -> HP48
0	No translation	No translation
1	char 10 -> chars 10,13	chars 10,13 -> char 10
2	Action 1 & translate  chars 128 - 159	Action 1 & translate \000 - \159 to HP48 chars
3	Action 1 & translate chars 128 - 255	Action 1 and translate \000 - \255 to HP48 chars

     To choose your favorite set, just type the number followed by the

     command TRANSIO on the HP48 command line.  Depending on which

     translation scheme you are using, the HP48 converts a different set

     of characters to PC ASCII format.  I would advise using option 3,

     since this forces the calculator to translate all symbols to pure

     ASCII (look for the table in page 27 - 16 of the HP48G series

     user's guide).  If you choose to use option 0 or 1, all characters

     from code 128 to 255 would be interpreted following the current

     code page of the PC setup - it will be unreadable!

     Also, if you are receiving ASCII files in your machine and you get

     a bunch of black squares, you can be fairly certain you are using

     translation mode 0, which makes the HP receive and store all

     newline characters (instead of eliminating them).

     Angle Mode:

     •  A(D) stands for degrees.

     •  A(R) stands for radians.

     •  A(G) stands for gradians.

     Fraction Mark:

        The HP48 can handle two types of fractions marks - the decimal

        dot or comma.  This option is available from the MODES input

        form (48G/GX) or menu 64.01.

        With regards to the ASCII header we have:

     •  F(.) means the format is dot.

     •  F(,) means the format is comma.

        If you try manually editing an ASCII file on the PC without a

        header, then try to send it to the HP48 using Kermit, you can

        obtain the following results:

Number format	Text sent	Result (object stored)
.	3.4	3.4
.	3,4	3 4
,	3.4	3 4
,	3,4	3,4

     As you would expect, sending files with ASCII headers to the HP48

     with mismatching fraction mark settings, leads to an "Invalid

     Syntax" error during transfer.

     Now take a look at rows 2 and 3 of the table above - the object

     received by the HP48 is stored as a program object without the <<

     and >> composed by two real numbers - well, that normally can't be

     done in User RPL!

     In fact the resulting object is a very simple System RPL program

     object (the internal language of the HP48).  The conclusion is that

     when a file is sent without an ASCII header, the HP48 translates

     numbers with mismatching formats into System RPL secondaries

     (programs) of the form:

          :: %IntegerPart %FractionalPart ;


Why do Kermit transfers seem to get slower?

  5.12.  Why do Kermit transfers seem to get slower?

  From: Dan Kirkland

  The reason the HP48 Kermit routines are so slow is because they are

  written in System RPL.  Everytime the HP48 receives a packet (received

  as a string), it copies the previously received packets (string #1)

  and the new packet (string #2) to a new string (which becomes string

  #1 when the next packet is received).  This is why the HP48 Kermit

  gets slower and slower on big transfers (string #1 just keeps getting

  bigger).

  As to sliding windows...  Sliding windows really don't help much with

  a clean, lag-free connection.  And as most people connect their HP48

  directly to the computer they are transfering to/from with a very

  short line, it is almost always very clean and lag-free.  So, sliding

  windows have very little to offer HP48 transfers.

  Yes, properly written Kermit routines should be at least as good as

  Z-Modem, even without sliding windows.  And with a dirty, lagged

  connection, Kermit with sliding windows will blow Z-Modem away.

  But then, this just doesn't happen very often with HP48 connections.

  Some claim that the HP48 can't do Z-Modem without tons of trickery

  because it doesn't have a large enough input buffer.  While this is

  true, it shouldn't be too hard to do.  And the same is true for Kermit

  if it is going to get Z-Modem type speed!  Small packets are more

  reliable, but much bigger packets are needed for speed.


Why does XRECV not work sometimes? (GX)

  5.13.  Why does XRECV not work sometimes? (GX)

  Pre-Rev R. G Series 48's had a bug that would sometimes cause XRECV to

  fail if there was not twice the amount of room free for the incoming

  file. FXRECV, a fix for this bug, is available on the Horn 9 disk in

  the directory \HP as FXRECV.  There is more info about this bug there

  as well.   Note that FXRECV is not required for Rom R, and in fact

  will not run properly on Rom R.


What do the funny symbols in this document mean?

  5.14.  What do the funny symbols in this document mean?

  The symbols in this document such as \-> and \GS+ are the ASCII

  representation of the special HP48 graphical characters.  See the

  section "Character Translations" in the manual for a complete table of

  symbols <--> ASCII representations.

     SX:

        Chapter 33 (Volume II if 2 volumes)

     GX:

        Page 27-16 HP48 G Series User's Guide


What are the pinouts for the HP48 serial connector?

  5.15.  What are the pinouts for the HP48 serial connector?

  Looking at the pins of the HP48 (the following diagram is showing the

  pins on the HP48, as you look at the calculator):

       Stated another way:

   HP48                  IBM 9 PIN               IBM 25 PIN

   (From the outside

    edge -> inward)

   SHIELD----------------   SHIELD----------------  SHIELD

   TX (Output)<---------- 2 RX (Input)------------3 RX (Input)

   RX (Input)-----------> 3 TX (Output)---------->2 TX (Output)

   SGND------------------ 5 GND-------------------7 GND

  This information is also on page 27-7 of the G/GX manual.


Is there any information on interfacing to the HP48?

  5.16.  Is there any information on interfacing to the HP48?

  HP has made available an UNSUPPORTED document called the "HP48 I/O

  Technical Interfacing Guide", which contains information on the wired

  and serial I/O hardware.  Also, there are a number of guides contributed

  by users on making your own serial/IR hardware.

  Look at  <ftp://hpcvbbs.cv.hp.com/dist/> as well as the other ftp

  sites listed in the Appendix.  If you find a good document, let me

  know so I can put it here!


How can I transfer programs/data from my HP-28S to my HP48?

  5.17.  How can I transfer programs/data from my HP-28S to my HP48?

  You use a program called "INPRT", which is available on GD #9.  Any

  previous version will crash the GX.  The new version's checksum is

  #EDF3h, and the old, SX-only version's checksum is #2280h.

  For each program that you want to transfer, you use the HP 28S to

  print it to the I/R output; INPRT, running on the HP48, reads the I/R

  output of the HP 28S and converts it into a program string.


Can I use rechargeable batteries with the HP48?

  5.18.  Can I use rechargeable batteries with the HP48?

  The Rayovac "Renewal" batteries have proven themselves to be reliable

  in the HP48, but there are some problems with Nickel Cadmium (Ni-Cad)

  batteries.   You'll have to decide if using rechargeable batteries is

  worth putting up with the problems associated with them:

  • You'll have to change batteries more often with rechargeable

     batteries.  Alkaline batteries can deliver power for a longer

     period of time, compared to rechargeable batteries.

  • Once the low-battery indicator comes on, you'll have to change the

     rechargeable batteries pretty quickly.  With rechargeable

     batteries, you have only a few minutes before the calculator dies

     (it's been said that you have up to 15 minutes or so).  With

     alkaline batteries, you have an amount of time that is supposedly

     measured in hours.

  • Ni-Cad batteries lose their charge with time, even if you are not

     using them.  Even if a Ni-Cad battery is just sitting unused on a

     shelf, it slowly loses its charge.  Alkaline batteries keep their

     charge for a very long time.


How can I tell, from within a program, if the battery is low?

  5.19.  How can I tell, from within a program, if the battery is low?

  The following 48 program reports the status of the ALERT annunciator.

  The ALERT annunciator is activated by alarms or low battery.

  This program is provided free of charge "as is" and has no warranty.

  No one is liable for any consequential damages.  Preston

       %%HP:T(3)A(D)F(.);

       \<<

       RCLF

       8 STWS #FFh #0h +

       #10Bh

       #6595Ah SYSEVAL

       #8h AND #0h >

       SWAP STOF

       \>>


I lost the information on my RAM Card when I changed the battery!

  5.20.  I lost the information on my RAM Card when I changed the

            battery!

  You forgot to turn ON the calculator before changing the battery.  The

  HP only supplies power to the RAM card while the HP is turned on.

  While the calculator is turned off, no power is supplied by the

  calculator, and all power comes from the RAM card battery.  If you

  then take out the battery from the RAM card while the calculator is

  turned OFF, the RAM card has no source of power, and you will lose all

  of the contents in the RAM card.


Why do I get an "Invalid card data" error when I merge a RAM card?

  5.21.  Why do I get an "Invalid card data" error when I merge a RAM

            card?

  This message is usually seen when you plug a brand-new RAM card into

  an HP48.  In this case, this message is normal and is harmless.  It

  just means that there was no (valid) data on the card.

     GX:

        This message can appear when a RAM card contains ports you have

        never used.  Press purple/left shift-LIBRARY. Hit NXT, then the

        PINIT softkey.  This will initialize all available RAM ports.

        It does not affect data already stored on the card.

        If you see this message under any other conditions, it could be

        one of the following:

        1. You took the battery out of the RAM card while the card was

           out of the calculator, therefore erasing the memory.

        2. You took the battery out of the RAM card while the card was

           in the calculator BUT the calculator was turned off.  Note

           that the calculator supplies power to the RAM card ONLY when

           the calculator is turned ON.  Again the memory on the card is

           gone.

        3. The RAM card battery is dead.

        4. There is a problem with either the calculator, the RAM card,

           or both.

        If the battery is operational, then try to store something on

        the card.  If you still get the error message, then backup all

        your info to a computer or another 48, and do a hardware reset.


I've heard about other manufacturer's RAM cards.

  5.22.  I've heard about other manufacturer's RAM cards.

            Will they work?

  While some cards may work, there is a chance that you may severely

  damage your HP48.  You should only use cards specifically designed for

  the HP48.  Naturally, HP sells such cards, and some third parties also

  make cards that will work in an HP48.  Some cards work with both the

  S/SX and the G/GX.  Some, however only work on the S/SX, or only on

  the G/GX.  Make sure that the card is designed to work for your

  version before using it.

     SX:

        The S/SX can only naturally support up to 128K per port.  HP

        sells 32K and 128K RAM cards.   However, TDS, using software

        "bank switches" produces 256K and 512K RAM cards.  These bank

        switching cards do not work in the G/GX series.  CMT is also

        makes 128K cards, which work in all HP48 calculators.

     GX:

        While you cannot use the TDS 256K and 512K cards, Sparcom has

        come out with 256K and 512K cards for the G/GX only.  HP also

        sells 1MB RAM cards that work for G/GX only.  The G/GX is able

        to accept a 4MB RAM card, but none are on the market at this

        time.


How does RAM card locking work?

  5.23.  How does RAM card locking work?

  From: Dave Arnett

  The HP48SX had three layers of write protection:

  •  The Seiko-Epson memory cards contain write protection.

      Seiko-Espon is the OEM manufacturer for HP brand cards.

      They developed the format, connector and pin definitions for the

      memory card interface.  We have a slightly modified version of their

      standard card where the low battery alarm limits are changed slightly.

      On an HP-branded RAM card, if you move the write-protect switch to

      the Protect position, two things happen.  First, the card itself

      ignores write cycles.  This is the first layer of defense for data

      integrity.  The card also changes the voltage level of one of its

      output pins to tell the HP that it is write-protected.

  •  The HP CPU chip detects the write protect indicator line of the

      card.  If it is reporting as unwriteable, the hardware locks out

      write functionality from the CPU chip.  This is the second layer of

      defense.  If this Card Detect line reports as writeable, then write

      transactions are permitted in hardware.  If the Card Detect line

      floats, the hardware reports that no card is installed.

  •  The HP system firmware checks the status of the write protection

      bits before writing to a memory card.  If the status bits indicate

      that the card is unwriteable (ROM or protected RAM), then the

      system code refuses to write to the card.

  In developing the HP48GX, we changed card handling in some significant

  respects.  I have recently posted information to the newsgroup on how

  the upper half of ROM and the card slot 2 are controlled through one

  pin of the Yorke CPU IC in a multiplexed fashion.  There are some

  details about the Yorke chip related to how various Saturn Bus deviced

  configure and unconfigure which required me to make the following

  hardware assignment changes:

Hardware Resource	HP48SX	HP48GX
CE1- Card Controller 1	Card 1	Bank Select Controller
CE2- Card Controller 2	Card 2	Card 1
CE3- Card Controller 3	Unused	Card 2
CDT1- Card Detect 1	Card 1	Card 2
CDT2- Card Detect 2	Card 2	Card 1

  Clearly, we had to assign Card Controllers and Card Detects in pairs,

  as much as possible.  Otherwise the hardware lockout would make a mess

  of things.

  A write protected RAM card in GX slot 1 has hardware lockout

  protection, since CDT2 can lock write actions to CE2.

  A write protected RAM card in GX slot 2 does not have the same HP

  hardware protection.  CDT1 is hardware coupled to CE1, which drives

  the Bank Select Controller.  Some may have wondered in my recent posts

  why the protocol for setting up bank settings uses READ operations

  rather than WRITE operations.  Now you know:  A WRITE operation to the

  Bank Select Controller would be ineffective if a ROM or Write-

  Protected RAM card is in Slot 2!

  The closest approximation to hardware write protection lies in the BEN

  (Bank Enable) line, which is bit 6 of the Bank setting.  Unless BE is

  set high, all attempts to access slot 2 are forbidden.  BEN is pin 10

  of the 74HC174 chip.  This line goes to pin 5 of the NAND chip to

  prevent Card Pin 21 from going active.

  The protocol in the HP48GX RPL Opertaing System implementation is to

  always leave BEN low, unless slot 2 activity is needed.  BEN should be

  set low again after card access is complete.

  So an HP48GX has three levels of card write protection as well:

  •  The card should prohibit Write activity if the protection switch is

      set.

  •  Slot 1 has the same hardware lockout as in the SX.  Slot 2 has a

      multi-step process necessary to enable access.

  •  The RPL system code checks the write-protect status before writing

      to a card.  It understands that CDT1 and CE3 map to card 2.


Why does the HP48 SX display flicker slightly?

  5.24.  Why does the HP48 SX display flicker slightly?

  Display flicker is usually caused by fluorescent lights.  The rapid

  pulsing of the fluorescent lights (60 Hz in the the U.S. and Canada),

  which is normally unnoticeable, interacts with the rapid pulsing/scanning

  of the HP48 LCD display (64 Hz refresh rate), which is also normally

  unnoticeable.  The 60 Hz fluorescent lights alias with the display

  refresh (64 Hz) to produce a 4 Hz "flicker".  It's normal and harmless.

  Outside the U.S. and Canada, power is supplied at a 50 Hz rate, not 60

  Hz.  This means that the display "flickers" at a 14 Hz rate, which is

  still noticeable.


I broke the LCD screen is there an easy way to get another?

  5.25.  I broke the LCD screen is there an easy way to get another?

  Unfortunately, as far as I am aware, you cannot get a replacement, the

  cheapest alternative is to send the calc in for "standard service" at

  HP, which is slightly cheaper than a new calculator.  Opening an HP48

  is quite difficult anyway.


How can I protect my LCD?

  5.26.  How can I protect my LCD?

  There are many ways to protect the HP48's LCD.  The solutions include:

  •  Inserting a piece of cardboard into the case.

  •  Cutting plexi-glass and putting it into the case (slightly better

      than cardboard).

  •  Buying a hard case from EduCalc.  A variety of types are available,

      including a hard leather case or a totally waterproof case.

  •  Keeping it in a video cassette or pencil case during transport.

  •  Using the cover from an old TI-8x calculator and fitting it into

      the grooves on the side of the HP48.  Some people have had some

      success with this, but I find it barely fits.


Is there a rigid (protective) case for the HP48?

  5.27.  Is there a rigid (protective) case for the HP48?

  An inexpensive solution to this is to go to Sears and get a Black

  Plastic Tool Box #9 65283 in the hardware deptartment.  It sells for

  only US $4.95.  The case is big enough for the calculator in it's

  case, plus extra batteries.

  The case is a good fit for the calculator.  If you want to go a step

  further, you can get some foam, glue it into the top and bottom halves

  of the case, and cut out a calculator shaped hole in the bottom.

  The result is lightweight, strong, secure and still leaves a little room

  for you to store extra batteries, a cable, and/or cards for your

  ports.

  An alternative is to purchase a case.

  Eric Finley <etfinley@ucdavis.edu> sells protective hard cases for

  the HP48.  They are stainless steel, very strong, and look nice.

  The cost is US $30. For more information, either e-mail Eric

  or check his web page at XXXXXX.


Can I use my Amateur Radio with my HP48?

  5.28.  Can I use my Amateur Radio with my HP48?

  Yes, however you need to have a few things, the first being an amateur

  radio license.  The next thing you need is a terminal node controller.

  If you are able to, get a terminal node controller that supports XON

  and XOFF software flow control.  This is good to have because the HP48

  only has a 256 character buffer.  When the buffer is full, the HP48

  sends the "buffer full" signal and a terminal node controller with

  software flow control can quit sending data until the HP48 can keep

  new data in the buffer.  If you don't have a terminal node controller

  with software flow control, you can still use it, but you may lose

  some data.

  The next thing you will want is some software to use with the terminal

  node controller.  You could make your own software using user-rpl

  commands such as BUFLEN, SRECV, and XMIT.  However, there is a

  plethora of software available.  All you need is software then can

  send and receive data from the serial port.  Here are a few programs

  that you might want to try:

Program	Location
term2	ftp.cis.com
hp48pack	Send mail to "info@arrl.org" with "get hp48pack" in the body of the message
dterm	ftp.cis.com/pub/hp48g/utilities/dterm.zip

  There is also a site that has a lot of hp48 programs relating to ham

  radio.  Connect to  <ftp://oak.oakland.edu/pub/hamradio/hp48/>

  Please inform the FAQ maintainer if you find additional software,

  so it can be added to this list.


Questions about programs

6. Questions about programs

6.1 Where can I get programs and information for the HP48 SX?

6.2 What are the Goodies Disks and where do I get them?

6.3 How do I get access to the HP Calculator BBS?

6.4 What are files that end with ".zip", ".Z" or ".gz"?

6.5 What is a "ship" file?

6.6 What is the ASC format and how can I use it?

6.7 What is the HYDE library, and how do I get rid of it?

6.8 What is the Minehunt game, and how do I use it?


Where can I get programs and information for the HP48 SX?

  6.1.  Where can I get programs and information for the HP48 SX?

  See Appendix E-1 for more info.


What are the Goodies Disks and where do I get them?

  6.2.  What are the Goodies Disks and where do I get them?

  See Appendix E-5 for more info.


How do I get access to the HP Calculator BBS?

  6.3.  How do I get access to the HP Calculator BBS?

  You can access the HP Calculator BBS via a modem.

       (208)-344-1691          2400 baud, 8N1

       (541)-715-3277          9600 baud, 8N1

  For those people who have access to the Internet, you can also access

  the BBS via  <telnet://hpcvbbs.external.hp.com> or

  <ftp://hpcvbbs.external.hp.com/dist/>

  See Appendix E-4 for more BBS sites.


note that this is a long distance call

for most people


What are files that end with ".zip", ".Z" or ".gz"?

  6.4.  What are files that end with ".zip", ".Z" or ".gz"?

  Files that end with ".zip" are pkzip archives, which originated in the

  MSDOS world.  One program that can extract the files in ".zip"

  archives is the Info Zip "unzip" program.

  Binaries and source can be found at

  <ftp://wuarchive.wustl.edu/systems/hp/hp48/Posting/unz50p1.exe>

  Files that end with ".Z" have been compressed using the Unix

  "compress" command.  To uncompress these files, you must use the

  "uncompress" command on Unix.

  Files that end with ".gz" have been compressed using the "gzip"

  compression command.  To uncompress these files, you must use either

  the "gunzip" or "gzip -d" command.  The "gunzip" program can also

  uncompress ".Z" files.  Binaries should be on all Unix systems, but if

  not you can try  <ftp://prep.ai.mit.edu/pub/gnu/> More information

  should be there on binaries for other platforms.


What is a "ship" file?

  6.5.  What is a "ship" file?

  In the past, programs for the HP48 posted on comp.sources.hp48 were

  posted in the "ship" format.  This format made it easier for the

  moderator to distribute programs, but made it more difficult for users

  to extract and use these programs.  Some people still use ship.

  To extract programs distributed in the "ship" format, you need the

  following:

  1. A copy of the "ship" program, compiled for your platform.

  •  Sources for ship can be found at

     <ftp://ftp.cis.com/pub/hp48g/dos/unship.zip> which also includes

     the DOS executable.

  •  Binaries for other platforms can be also be found at

     <ftp://wuarchive.wustl.edu/systems/hp/hp48/Posting/>

  2. A copy of the latest InfoZip "unzip" program or an unarchiver that

     understands the pkunzip v2.04g format.  Note that you cannot use

     older unzip programs, as old unzip programs do not understand the

     new compression formats.  See the previous section for information

     on where to get source and binaries.

  Once you have a copy of the "ship" and "unzip" programs, you use

  "ship" to convert the ship-encoded file into a .zip file, and you use

  the "unzip" program to extract the HP48 files from the ".zip" file.


What is the ASC format and how can I use it?

  6.6.  What is the ASC format and how can I use it?

  The functions ASC\-> and \->ASC were written by William Wickes to

  facilitate transferring HP48 binary objects in an ASCII format.

  Some HP48 objects, like libraries, cannot normally be converted into

  ASCII, unlike program objects, and these functions make it possible to

  do so.

  The \->ASC function converts the object in level 1 into an ASCII

  string, which can then be uploaded to a computer for mailing.

  The ASC\-> function converts the string object in level 1 back into an

  object.  A checksum is used to ensure that the decoding is correct.

  A copy of these programs are given in Appendix A-1, near the end of

  this file.  Note however, that these functions aren't used much

  anymore.  The standard in the newsgroup seems to first zip the

  programs together and post them uuencoded.  But, you may still need

  these utilities for extracting older files you download.


useful when transferring objects via electronic mail or bulletin boards


What is the HYDE library, and how do I get rid of it?

  6.7.  What is the HYDE library, and how do I get rid of it?

  The HYDE library is a library that changes the messages on your HP48.

  It works on all versions of the HP48 and is available on Goodies Disk

  2.  The program is in the DNICKEL directory needs to be converted

  with ASC\->.  The instructions for the program are in the HORN2 directory.

  The library is 3679.5 bytes, small enough to keep on your HP48 so you can install

  it on a friend's when they're not looking.

  Follow the previous instructions for installing the library, then go to the library menu

  and run HYDE.

  However, getting rid of the HYDE library is a little trickier.  First you must

  type JEKY on the command line.  This will disable the HYDE library and

  restore the standard set of messages.  Then you can follow  the normal

  instructions for deleting a library.


HYDE.TXT


HYDE.DOC


What is the Minehunt game, and how do I use it?

  6.8.  What is the Minehunt game, and how do I use it?

  The Minehunt game is a game built in to the G/GX.  It was also

  included on the HP Equation-Library Card (for the HP48 SX).

     GX:

        It is located in the UTILS menu of the left-shift(purple) EQ LIB

        menu.  (Left-Shift {EQ LIB], {UTILS}, {MINEHUNT}).  See page

        25-14 of the manual for a game explanation and picture.

     SX:

        It is located in the UTILS library.

  You can save a game by pressing the STO button. This creates a

  variable with the name MHpar. If you are in the directory containing

  that variable, you will resume your old game when you run MINEHUNT.

  To select the number of mines for your next game just store a number

  in a variable, Nmines (it's case sensitive), and you'll get that many

  mines.  If you store a negative number, you'll get the absolute value

  of that many mines, AND all mines will be visible.

  You can also move diagonally if you use the numbers as arrows.


Numbers as Arrows

    1 is down+left

    2 is down

    3 is down+right

    4 is left

    6 is right

    7 isup+left

    8 is up

    9 is up+right.


Questions about programming and advanced user functions

7. Questions about programming and advanced user functions

7.1   I've heard the names RPL, Saturn, STAR, GL etc... What are they?

7.2   Is there a C compiler for the HP48?

7.3   Why do SysRPL programs run faster than UserRPL programs?

7.4   What is a good reference for learning SysRPL and ML?

7.5   Can I make my own Libraries? Can I Split Others?

7.6   How do I know what library ID number to use for my program?

7.7   What information is there on the internals of the HP48?

7.8   Where can I get some programming development tools?

7.9   I know UserRPL. How do I get started in SysRPL?

7.10 Are there any viruses for the HP48?

7.11 How do I store fields of variable length effectively?

7.12 What is "Vectored Enter", and how do I use it?

7.13 What is "WSLOG"?

7.14 What are SYSEVALs?

7.15 What are some useful SYSEVALs?

7.16 What are LIBEVALs?

7.17 What are some useful LIBEVALs? (GX)

7.18 What is the format of a GROB object?

7.19 What is the AUR and what information does it contain?

7.20 What is the syntax for INFORM, CHOOSE, and MSGBOX? (GX)

7.21 How do I put checkfields in my INFORM menus?


I've heard the names RPL, Saturn, STAR, GL etc...

  7.1.  I've heard the names RPL, Saturn, STAR, GL etc...

          What are they?

  ASAP

     This is a simple Saturn assembler, written in the Perl language.

  Chip8, Chip48, Schip, Schip8

     This is a machine-code program that was inspired by the chip8

     video game interpreter for the RCA CDP1802 microprocessor

     several years back.  Chip8 allows you to write a simple

     graphics-based video game for the HP48 SX.  Among the games

     written are "clones" of Breakout, PacMan, and Pong, to name a

     few.

     Chip48, Schip and Schip8 are two different names for an enhanced

     version of chip8 specifically designed for the HP48 SX.  People

     have written programs to assemble Schip assembly language into a

     form directly usable by Schip on an HP48.  Schip interpreters

     are available for both G and S series.

  GL

     Game Language is a language for the programmer who wants

     almost the speed of assembly, but who doesn't want to spend a

     lot of time and effort to learn all the tricks of assembly

     programming on the HP48. GL has an assembly-like syntax, and

     there is an assembler for PC and one for the HP48 itself. Since

     GL is an interpreter, the GL library (3 KB in size) must be

     installed on the HP48 to run GL programs. The instruction set is

     powerful, with sprites and pixel based graphics, scrolling,

     sound, keyboard control, and more. There are 256 1-byte

     registers which can be used in pairs as 2-byte words. A GL

     program can be up to 64 KB in size.  GL was inspired by SCHIP,

     but it is much better in all aspects.  It is suitable for many

     applications, not only games, that require high speed.  Of

     course it works on both the HP48 S/SX and the G/GX.  GL is

     written by Erik Bryntse.

  ML

     Machine Language.  This is usually used in reference to HP48

     assembly language programming.

  MLDL

     Machine Language Development Library.  This is a library that

     allows you to debug machine language programs with only an HP

     48.

  PDL

     "Program Development Link".  This is an DOS program, sold by

     Hewlett-Packard, that allows you to write and develop HP48

     applications from your IBM PC clone.  Programs are written on

     your PC, transferred to the HP48, and tested from your PC (and

     not the HP48).

  RPL

     RPL is the name of the language used to program the HP48 and

     HP-28 series calculators.  RPL stands for "Reverse Polish Lisp".

     It's interesting to note that an HP Journal article incorrectly

     described RPL as "ROM-based Procedural Language".

  SASS

     SASS is a simple Saturn assembler, written in C/yacc (BSD Unix &

     Bison).  It uses Alonzo Gariepy's mnemonics.

  Saturn

     "Saturn" is the internal code name for the processor used in the

     HP48, HP-28 series, and many other calculators (just about all

     HP calculators since the HP 18/28 series).

  STAR

     This is the "Saturn Macro Assembler" (how "STAR" comes from

     this, I don't know), an assembler that uses mostly Alonzo

     Gariepy's mnemonics.  It's written in C and runs on many

     different machines (PCs, Amigas, Unix, etc.).  STAR is available

     via anonymous ftp from

     <ftp://hpcvbbs.cv.hp.com/dist/unix/star-1.04.4.tar.gz>

  System RPL

     This is the name for the custom "operating system/language" used

     to program the CPU used in the HP48 calculator.  System RPL is a

     superset of the normal user RPL commands; in addition to the

     normal, user-accessible RPL commands, system RPL includes many

     lower-level functions.  System RPL is a language one step higher

     than assembly language.

     HP has released a system development toolkit (for the IBM PC)

     containing a system RPL compiler, assembler, and loader,

     complete with a couple hundred pages of documentation.  This

     toolkit, while copyrighted, is, for the most part, freely

     copyable.  If you can find a BBS or archive site that has it,

     you can download all of the system RPL files and documentation.

  USRLIB

     USRLIB is a program that takes the contents of an HP48 directory

     and turns it into a library object.  It currently runs under

     MSDOS.

  Voyager

     Voyager is an "interactive disassembler" for IBM PC clones that

     disassembles HP48 SX RPL and machine code.  You download a copy

     of the RAM and ROM in your HP48 SX to your PC, and run Voyager.

     Using Voyager, you can then view the disassembled or unthreaded

     code.  Unfortunately (or fortunately), Voyager uses the HP

     mnemonics, and not Alonzo Gariepy's mnemonics.  Voyager is

     available from the HP BBS <ftp://hpcvbbs.cv.hp.com/dist/>, and

     from various bulletin boards (the HP handhelds forum in

     CompuServe also has a copy).  The latest version is "1.07".


Is there a C compiler for the HP48?

  7.2.  Is there a C compiler for the HP48?

  Yes.  Alex Ramos has written a GNU C back end for the Saturn

  processor.  Binaries are available for both Linux and Windows 95/NT,

  and source is available for compilation on other platforms.

  Check  <http://www.cris.com/~ramos/hp48/hp48xgcc.htm> for the latest

  version.


Why do SysRPL programs run faster than UserRPL programs?

  7.3.  Why do SysRPL programs run faster than UserRPL programs?

  SysRPL is the built in language, custom designed for the Saturn

  processor used the HP48 family.  UserRPL is a "subset" of SysRPL.  The

  main reason for the speed difference is the fact that UserRPL commands

  have built in argument and error checking.  In SysRPL, the programmer

  is responsible for all error checking to avoid memory clears.

  Note that System RPL is a compiled language and that therefore you

  need a program like Jazz or GNU-Tools to create it.  This means you

  can't edit or view SysRPL on the HP48 directly, unlike UserRPL.

  However both can be run the same way.


What is a good reference for learning SysRPL and ML?

  7.4.  What is a good reference for learning SysRPL and ML?

  Jim Donnelly's book "An Introduction to HP48 System RPL and Assembly

  Language Programming" provides 230 pages of step by step instructions

  for new programmers with plenty of examples.  It also comes with a 3.5

  inch disk containing the examples in source form and HP's development

  tools for DOS.  Available through EduCalc for $25 U.S.

  The ISBN number is: 1-879828-06-5

  Also useful are RPLMAN.DOC and SASM.DOC available on Goodies Disk 4.

  See Appendix E-5 for more information.  You might want to also have a

  look at the following URL:

  <http://titan.cs.uni-bonn.de/~wolfrum/hpbooks.html>


Can I make my own Libraries?  Can I Split Others?

  7.5.  Can I make my own Libraries?  Can I Split Others?

  Yes, you can either use USRLIB in HP's development tools to create

  libraries in DOS, or you can make them right on your HP with hacking

  utilities like Rick Grevelle's D->LIB and L->DIR which can both create

  and split libraries from/to directories.  These can be found in Mika

  Heiskanen's HACK library at  <http://www.hut.fi/~mheiskan/>


How do I know what library ID number to use for my program?

  7.6.  How do I know what library ID number to use for my program?

  Note: While this document says HP48 SX, it is also valid for GX.

  HP48 SX Library ID Numbers Paul Swadener, HP Developer Support.  03

  Sep 1993

  The HP48 will become confused if two or more libraries currently in

  the machine have the same ID numbers. To help third party developer

  efforts, HP maintains a list of HP48 Allocated Library ID Numbers.

  Here are the "rules". The penalty suffered from not following these

  rules is that your library may not work if another library is in the

  machine with the same number.

  Hope this helps clear up how library numbers work.


Rules

1. Don't use any number in the range 000h through 300h.

    These are reserved for HP's use.

2. Don't use any number in the range 301h through 5A0h

    unless you have been assigned  that number by HP.

    These numbers are reserved for developers who

    are in the business of distributing their  software, that is,

    Independent Software Developers.

    To apply for the allocation of an ID# contact

    Paul Swadener

    Hewlett-Packard Company

    1000 NE Circle Blvd., Corvallis, OR 97330,

    fax number: 541-715-2192

    internet address: paul_swadener@hp6400.desk.hp.com.

    You must be a registered developer and supply

    the name/nature of your product, and current shipping

    address and phone/fax/internet add./etc.

3. Use a number in the range 5A1h through 600h for

    experimental work and software. HP does not track

    the use of these numbers.

4. Use a number in the range 601h through 6F6h for

    your personal applications, those which you will share,

    if at all, only to a known set of other users for personal

    uses. HP does not track the use of these numbers.

5. Don't use any number in the range 6F7 through 6FF,

    as these numbers were allocated before the formal

    allocation process in was instituted.

6. Don't use any number above 700h. These are also

    reserved for use by HP.


What information is there on the internals of the HP48?

  7.7.  What information is there on the internals of the HP48?

  The most important documents are part of the "System RPL" development

  tools, a completely unsupported set of IBM PC tools created by HP

  Corvallis.  The tools, which run on DOS machines only, contain documentation on:

  •  System RPL (which includes information on HP48 SX display graphics,

      keyboard control, etc.).

  •  Saturn assembly language, including information on a Saturn assembler.

  •  A system RPL compiler.

  •  A Saturn object file linker.

     However the documentation is also useful for some of the newer

     program development tools such as Jazz and GNU-Tools.  (See the

     next question on where to obtain these).


       the creators of the HP48


"Saturn" is the name of the CPU in the HP48


Where can I get some programming development tools?

  7.8.  Where can I get some programming development tools?

  HP's unsupported System RPL development tools and documentation are

  available to customers free of charge to help them in HP48 application

  development, subject to certain legal terms, which are given with the

  tools (they're too long and detailed to give here).

  You can get a copy in one of the following ways:

  •  Anonymous ftp to  <ftp://hpcvbbs.external.hp.com/dist/>

  •  Get Goodies Disk 4.  For info, see Appendix E-5.

     Alternatively, you can use one of the packages put together by

     members of the HP community.  In particular, Jazz is a library by

     Mika Heiskanen which allows you to program in System RPL and

     Machine Language directly on your HP48!  It requires either an SX

     with a RAM card, or a GX.

  Jazz is available at  <http://www.hut.fi/~mheiskan/>

  There also is GNU-Tools by Mario Mikocevic (Mozgy) which is set of

  replacements for HP's development tools that not only runs on DOS, but

  also typical Unix systems such as Linux and Solaris.  It is

  distributed in both source and binary form.

  GNU-Tools is available at:

  •  <ftp://gnjilux.cc.fer.hr/pub/hp48/gtools/>

  •  <http://www.zems.fer.hr/~mozgy/jwz/hp48.html>


I know UserRPL.  How do I get started in SysRPL?

  7.9.  I know UserRPL.  How do I get started in SysRPL?

  Here is a quick guide to learning System RPL.  See the other questions

  for more information on where to obtain the items below.

  •  Learn UserRPL first, and become familiar with most commands.

  •  Get Goodies Disk 4 (HPTOOLS) or GNU-Tools if you have Linux etc...

  •  Get the new release of supported entries, available with GNU-Tools

      (not the entries in Goodies Disk 4).

  •  Read RPLMAN.DOC and/or get Jim's Donnelly book; it makes things

      easier.

  •  Get ENTRIES.SRT from the HP48 IRC channel.

  •  Get the tables from the SAD package by ftp to hpcvbbs.cv.hp.com

  •  Get Jazz for your HP when you are ready.

  •  You can learn a lot by studying the ROM and other people's programs

      with Jazz!


Are there any viruses for the HP48?

  7.10.  Are there any viruses for the HP48?

  There are several, and most are French.  In the United States, a virus

  called the "Michigan virus" erupted a couple of years ago.  There is a

  program on Goodies Disk 8 that checks for the Michigan Virus.

  Currently, viruses do not pose an appreciable threat on HP48's.


How do I store fields of variable length effectively?

  7.11.  How do I store fields of variable length effectively?

  See Appendix A-5 near the end of this file.


What is "Vectored Enter", and how do I use it?

  7.12.  What is "Vectored Enter", and how do I use it?

  From: Bill Wickes

  The HP48 manuals do not document a very powerful feature that we call

  "Vectored ENTER", that allows you in effect to redefine or bypass the

  command line parser and to have a shot at the stack etc. after the

  command line has been executed.

  Keys that execute an automatic ENTER perform a two-step process:

  1. The command line is parsed and evaluated.

  2. The key definition is executed.

  When flags -62 and -63 are both set, the system extends this

  process as follows:

  1. The current path is searched for a global variable named *aENTER

     (where "*a" is the Greek alpha character--character 140).  If

     present, the command line is entered as a string object and *aENTER

     is executed.  If absent, the command line is parsed and evaluated

     normally.

  2. The key definition is executed.

  3. The current path is searched for a global variable named *bENTER

     ("*b" is Greek beta--character 223).  If present, then a string

     representing the key definition is put on the stack, and *bENTER is

     executed.  The string is the key definition object's name if it is

     a command, XLIB name, global or local name, or an empty string for

     other object types; its primary purpose is to implement things like

     the TRACE mode on other calcs, where you can print a running record

     of what you do.

     A simple example of the use of *aENTER is to create a more

     convenient binary calculator, where *aENTER slaps a "#" on the

     front of the command line so you don't have to bother when entering

     numbers.


What is "WSLOG"?

  7.13.  What is "WSLOG"?

  It is an until recently undocumented feature which stands for "Warm Start Log".

  Type in WSLOG in caps, and calc will list the time and cause of the

  last four warm starts.  This feature helps HP technical support to fix

  your HP48 in case it crashes.

       0 - log cleared by <ON> <SPC> then <ON>

       1 - low battery condition, auto deep sleep mode invoked to save battery

       2 - hardware failed during IR (time out)

       3 - run through address 0

       4 - system time corrupt

       5 - deep sleep mode wake up (alarm?)

       6 - unused

       7 - CMOS test word in RAM was corrupted

       8 - abnormality was detected about device config

       9 - corrupt alarm list

       A - problem with RAM move

       B - card module pulled

       C - hardware reset

       D - system RPL error handler not found in run stream

       E - corrupt config table

       F - system RAM card pulled


it is listed in the command appendix of newer G manuals,

as well as being fully explained in the AUR


What are SYSEVALs?

  7.14.  What are SYSEVALs?

  SYSEVALs are addresses that point directly to a location in the HP48's

  ROM. Many SYSEVAL hex strings are System-RPL commands.  Because there

  is no argument checking, it very easy to clear your HP48's memory.

  In the file SYMBOLS.GX, HP designates three types of entries.  The

  first type is "supported."  This means that a particular entry will

  work on ALL versions of the HP48 and HP supports the use of this

  entry.

  The second type of entry is "unsupported".  This means that HP does

  not support the use of this entry and it will not be the same on all

  versions of the HP48.

  The third type is "unsupported-static."  This is an entry to HP does

  not support the use of, but it is the same for all versions.


What are some useful SYSEVALs?

  7.15.  What are some useful SYSEVALs?

  For a complete list of supported entry points, see

  <http://www.hut.fi/~mheiskan/>

  In System-RPL, different HP object types are referred to by symbols.

  These symbols are used to construct stack diagrams, which tell the

  user how to use System-RPL commands.  Here are some of the symbols:

Symbol	Type	Example
$	string	"ABCDEFG"
id	Global Name	'A'
arry	Array	[[ 1 2 ] [ 3 4 ]]
grob	HP48 Graphics Object	Graphic 131x64
#	Binary Number	<1h>
symb	Symbolic Object	'A^2+B^2'

     To interpret the stack diagram:

        Everything on the left of the -> arrow is the input.  That needs

        to be on the stack before executing the SYSEVAL.  The symbols

        show you which kinds of data to put on the stack.  Once you

        execute the syseval (see next paragraph), the HP will return the

        data back that is indicated on the right side of the arrow.

     To use the following entries, do the following:

        1. Make sure (triple check) that the appropriate arguments are

           on the stack.

        2. Push Right-shift /, you should get a # on the command line.

        3. Enter the hex string exactly as shown in the hex string

           column.

        4. Put an small case h at the end of the hex string.

        5. Press enter.

        6. Type SYSEVAL.

  Here are just a few examples:

Hex	Sys-RPL Name	Category	Stack Diagram
15777	NULLID	Supported	( -> '' )
30794	VERSTRING	Supported	( -> "HPHP48-?" )
3A328	MakeStdLabel	Supported	( $ -> grob )
3A3EC	MakeDirLabel	Supported	( $ -> grob )
3A38A	MakeBoxLabel	Supported	( $ -> grob )
3A44E	MakeInvLabel	Supported	( $ -> grob )
3A1FC	DispMenu.1	Supported	( -> )
05F42	GARBAGE	Supported	( -> )
41F65	WaitForKey	Supported	( -> #KeyCode #Plane )
353AB	SYMB>IDS	Unsupported-Static	( symb -> list )
40D25	LockAlpha	Supported	( -> )
40D39	UnlockAlpha	Supported	( -> )
3AA0A	1A/LockA	Supported	( -> )
44C31	DoNewMatrix	Supported	( -> arry )
44FE7	DoOldMatrix	Supported	(arry -> arry' T/F )
1314D	TOADISP	Supported	( -> )
13135	TOGDISP	Supported	( -> )
39531	ClrDA1IsStat	Supported	( -> )
130AC	RECLAIMDISP	Supported	( -> )
4E347	TURNMENUON	Supported	( -> )
05B15	$>ID	Supported	( $ -> id )
05BE9	ID>$	Supported	( id -> $ )
3A1E8	DispMenu	Supported	( -> )
39BAD	DispStack	Unsupported-Static	( -> )


What are LIBEVALs?

  7.16.  What are LIBEVALs?

  From: Joe Horn (Copied from "libeval.doc" on GD 9)

  The G/GX has a new command: LIBEVAL.  It's sort of like SYSEVAL, but

  instead of taking a memory address (which could be ambiguous due to

  the G/GX's massive need for bank switching), it takes XLIB numbers.

  It's a "back door" for us hackers.  Unlike the ELSYSEVAL command in

  the HP Solve Equations Library Card, which only worked for the

  libraries in that card, LIBEVAL works for any library, including the

  hidden ones in the operating system.

    CAUTION:	LIBEVAL, like SYSEVAL, is both powerful and dangerous.

If used with incorrect input(s) and/or in the wrong

environment, it can nuke your memory.

  LIBEVAL takes a single user binary integer of the form #LLLFFFh, where

  LLL is the library ID (hex), and FFF is the three-digit function num-

  ber (hex, with leading zeros if necessary).

  For example, the R->B command is XLIB 2 9.  So you can perform a R->B

  by executing #2009h LIBEVAL.  Try it: 10 #2009h LIBEVAL -> #Ah.

  Using it for named commands is unnecessary, but the G/GX is highly

  XLIB oriented (again, due to the need for bank switching), and there

  are many useful and interesting features accessible only through

  LIBEVAL.

  A prime example is the G/GX's inability to programmatically launch the

  new "dialog boxes".  Suppose a program needs to print things; it would

  be awfully nice to be able to throw the I/O PRINT dialog box onto the

  screen.  The User's Guide is no help here, and in fact it would seem

  impossible to do.  But #B4197 LIBEVAL is all it takes!  Try it.  Cool,

  huh?


What are some useful LIBEVALs? (GX)

  7.17.  What are some useful LIBEVALs? (GX)

  See Appendix B-3 for a few GX LIBEVALs.


What is the format of a GROB object?

  7.18.  What is the format of a GROB object?

  Note: I received two very good answers to this question, and each

            cater to a different kind of user, so I will include them both.

     The easy way:

        First, add pixels to the right-hand edge to make the horizontal

        dimension a multiple of 8, then separate the object horizontally

        into groups of four pixels.  Suppose, for example, you want to

        make this into a 22x8 GROB:

          ---------****---------

          --------**--**--------

          -------**----**-------

          ********------********

          ********------********

          -------**----**-------

          --------**--**--------

          ---------****---------

     You would break it up like this:

          ---- ---- -*** *--- ---- ----

          ---- ---- **-- **-- ---- ----

          ---- ---* *--- -**- ---- ----

          **** **** ---- --** **** **--

          **** **** ---- --** **** **--

          ---- ---* *--- -**- ---- ----

          ---- ---- **-- **-- ---- ----

          ---- ---- -*** *--- ---- ----

     Notice, I've added two columns of pixels to make it 24x8.  Now,

     each group of four can be represented by a hexadecimal digit.

---- 0	--*- 4	---* 8	--** C
*--- 1	*-*- 5	*--* 9	*-** D
-*-- 2	-**- 6	-*-* A	-*** E
**-- 3	***- 7	**-* B	**** F

     Now, replace each group of four pixels with its corresponding

     hexadecimal digit: 00E100  003300  081600  FF0CF3  FF0CF3  081600

   003300  00E100.

     So, your final grob is:

     GROB 22 8 00E100003300081600FF0CF3FF0CF308160000330000E100

     The technical way:

        1. Every HP object format is described in RPLMAN.DOC, see this

            file for more info.

        2. All HP objects are (of course) nibble based.  When viewing

            them on the PC, which is byte based, the low order nib is

            always read and written first.

        3. HP objects begin with a 5 nib prologue which identifies the

            object type (and other things).  This is the prologue for a

            grob object..

             02B1E pr HP:DOGROB

             02B1E @  Graphic prologue (/U GROB)

        4. Every 5 nib sub field of an object, such as prologue, length,

            etc., is read in reverse order (low nib first).  The grob

            prologue would appear E1B20, or 1E 2B x0 in a hex dump on a

            PC.  The least significant nibble of the next field begins

            right at the x in x0.

        5. It is customary to always work with HP objects on the PC with

            the HPHP48-E header (substitute your favourite rom version

            letter) preceeding the prologue.  This gives no hassles when

            downloading via Kermit or X-Modem.

        PC hex dump of a grob object.. ( remember each 5 nib field is

        reverse order )

        1. "HPHP48-E" 8 byte ascii string with msb off

        2. 5 nib prologue, 02B1E (hex)

        3. 5 nib length field, includes length of body AND length and

            height fields!  does not include 5 nib prologue.  So, the

            total #nibs the grob object takes in HP memory is this number

            + 5.  Important!

        4. 5 nib height field  ( yes, it is height then width )

        5. 5 nib width field

        6. body (described below)

        The grob object looking at it using command line EDIT on the

        HP..

          GROB <width (dec)> <height (dec)> < body >

     The body is exactly the same looking at it on a PC hex dump or on

     the command line EDIT.  Just remember to read low nibble first for

     hex dump.

     Because of hardware restrictions, the number of nibs required to

     represent one horizontal line must be even (byte aligned).  So, use

     this method to calculate the number of nibs in one line..   (pascal

     example)

          nibs := width div 4;

          if nibs mod 4 <> 0 then nibs := nibs + 1;

          if odd(nibs) then nibs := nibs + 1;

     Then to get the #nibs in the entire body, multiply it by the

     height.  Remember, the length field must be this total body length

     + 15 !

     For example, a 131 wide grob requires 34 nibs for one horizontal

     line, where 5 of the bits are unused.  The first nib in the second

     line begins at nib 35 for this grob, etc...  If the grob is 64

     lines, then the body is 2176 nibs.  Add 5 for the prologue, 5 for

     the length field, 5 for height, and 5 for width.  Total object size

     (on the HP) is 2196 nibs, or 1098 bytes.  The length field should

     contain 2196 minus 5 for prologue = 2191 (0088F hex)

     Note that for each nib, the right-most bit is the left-most pixel

     on the screen.  This is nearly always the case for graphic memory.


What is the AUR and what information does it contain?

  7.19.  What is the AUR and what information does it contain?

  From: Jarno Peschier <jpeschie@cs.ruu.nl>

  In this text I will try to answer a number of frequently asked

  questions about the HP48 G Series Advanced  User's Reference Manual.

  In the remainder of this text I will use the common abbreviation AUR

  when referring to this book.

  The questions I will try to answer are:

  •  What is the AUR?

  •  What information does the AUR contain?

  •  Do I need the AUR?

  •  Why didn't HP supply the AUR with every HP48?

  •  Where can I get the AUR?

  •  Does the AUR contain any SYSEVALs and/or LIBEVALs?

  •  Does the AUR say anything about SysRPL and/or ML?


     What is the AUR?

    The AUR is just what it's name tells you it is: it's a reference

    manual for the HP48 G Series.  It has the same outside

    appearance as the  HP48 G Series User Guide (the manual you get

    with your HP48 G or HP48 GX when you buy it), except that it's

    much thicker (just under 4 cm).  The AUR contains about 650

    pages of useful information about your calculator.


     What information does the AUR contain?

    The AUR contains information about UserRPL programming, quite a

    lot of programming examples, a complete command reference for

    all the (UserRPL) commands the G Series knows and reference

    lists about all equations, error and status messages, units,

    etc...  Of course it has an extensive index at the back of the

    book.

        Chapter 1: Programming

           Contains: Understanding Programming, Entering and Executing

           Programs, Viewing and Editing Programs, Creating Programs on

           a  Computer, Using Local Variables, Using Tests and

           Conditional Structures, Using Loop Structures, Using Flags,

           Using Subroutines, Single-Stepping through a Program,

           Trapping Errors, Input, Stopping a Program for Keystroke

           Input, Output, Using Menus with Programs, Turning Off the

           HP48 from a Program.

        Chapter 2: Programming Examples

           Contains: Fibonacci Numbers, Displaying a Binary  Integer,

           Median of Statistics Data, Expanding and Collecting

           Completely, Minimum and Maximum Array Elements, Applying a

           Program to an Array, Converting Between Number Bases,

           Verifying Program Arguments, Converting Procedures from

           Algebraic to RPN, Bessel Functions, Animation of Successive

           Taylor's Polynomials, Programmatic Use of Statistics and

           Plotting, Trace Mode, Inverse-Function  Solver, Animating a

           Graphical Image.

        Chapter 3: Command Reference

           This chapter contains one entry for every command (except for

           RULES) from ABS to ZVOL and  + to  ->.  Each entry contains:

        •  A description of what the command does (with stack diagrams).

        •  Ways in which you can access it from the keyboard (with

            submenu you need, or if you can only type it in in Alpha-

            mode).

        •  Which flags the command is affected by.

        •  Remarks, and a list of related commands.

           Often a command has one or more example programs too. This

           chapter is the bulk of the whole book; it's 424 pages thick.

        Chapter 4: Equation Reference

           This chapter contains one entry for every section in the

           built in Equation Library (EQLIB).  Each entry contains: a

           table of used variables and then for every set of equations

           an entry with some more info about the equation set, the

           picture that goes with it (if any), all the equations and one

           or more sets of example numbers and solutions.  The end of

           the chapter has a list of references from which all the

           equations were taken.

        Appendix A: Error and Status Messages

           This chapter contains two tables with all possible messages.

           The first has them sorted alphabetically and shows the

           message, the meaning and the ERRN number in hex.  The second

           has them sorted on ERRN number (and thus on category) and

           only contains the number in hex and the message itself.

        Appendix B: Table of Units

           This chapter contains a table with all units the HP48 G

           Series knows.  It contains the unit (both the name you use on

           the calculator as well as the full name) and the value it

           represents in SI units.

        Appendix C: System Flags

           This chapter contains a table with all the system flags of

           the HP48 G Series.  The table contains the number followed by

           a description of it's use and the results you get when the

           flag is set or clear.

        Appendix D: Reserved Variables

           This chapter contains a table with all the reserved variables

           of the HP48 G Series (ALRMDAT, CST, "der"-names, EQ, EXPR,

           IOPAR, MHpar, Mpar, n1/n2/..., Nmines, PPAR, PRTPAR,

           s1/s2/..., VPAR, ZPAR, SigmaDAT and SigmaPAR) with complete

           information about what they are used for and about all

           possible parameters that can be put into them.

        Appendix E: New Commands

           This chapter lists all the commands that are new to the HP48

           G Series, with a brief description of what the commands do.

           A list like this can be found elsewhere in the HP48 FAQ list

           as well.

        Appendix F: Technical Reference

           Contains:  Object sizes, Mathematical simplification rules

           used by the HP48, Symbolic differentiation patterns used by

           the HP48, the EquationWriter's expansion rules, References

           used as sources for constants and equations in the HP48

           (other than those in the Equation Library).

        Appendix G: Parallel Processing with Lists

           This chapter contains info on parallel processing that makes

           UserRPL look even more like a real functional programming

           language by letting (almost) all the commands  function on

           lists of parameters as well (i.e. adding map capabilities to

           all internal commands).


     Do I need the AUR?

    Yes, you do.  In my humble opinion the AUR is just "The Manual,

    Part II" and every owner of a HP48 G or HP48 GX should have it,

    especially if you are (going to be) programming in UserRPL for

    any reason.  A lot of the frequently asked questions that pop up

    on comp.sys.hp48 are simply questions that are meant to be

    answered by the AUR.


     Why didn't HP supply the AUR with every HP48?

    Since you're reading this FAQ, you're probably gifted: you are

    not an average HP48 user.  The set of "average users" probably

    consists mostly of people that simply never program their HP48

    in any way ("Wow, can it do that too?!").  In this case, they

    will never take one look at the AUR ever again, and since this

    is quite a thick book it would be a waste of money, trees, the

    environment, transportation costs, etc... to supply the AUR in

    every box.  This is probably why HP made it an extra accessory

    for those people that "really need" it.  I think...


    Where can I get the AUR?

    You should be able to buy (or order) it from the same shop where

    you purchased your calculator.  The HP part number is 00048-

    90136.  The book does not seem to have an ISDN number; it's a HP

    part, not a book.


     Does the AUR contain any SYSEVALs or LIBEVALs?

     Yes, it contains exactly one.  The example for the SYSEVAL

     command tells you that #30794h SYSEVAL gives you the version of

     your HP48.  My HP48 GX rev. P gives "HPHP48-P".


       No, it doesn't.


What is the syntax for INFORM, CHOOSE, and MSGBOX? (GX)

  7.20.  What is the syntax for INFORM, CHOOSE, and MSGBOX? (GX)

  Based on a posting on HPCVBBS by Cary McCallister.  Revised by Joe

  Horn.  Re-formatted by Andre Schoorl.

     INFORM - Create a Custom Input Form

        INPUT:

             5: "title"

             4: { fields }

             3: <format>

             2: { reset_values }

             1: { initial_values }

        OUTPUT:

             Either: 2: { new_values }

                        1: 1

             or:       1: 0

        PURPOSE:

           INFORM creates full-screen custom input forms, similar to

           those of the built-in applications.

        ARGUMENTS:

           title

              Is displayed in font 1 (small) at the top centre of the

              screen.  It may contain any number of characters,

              including 0, but, at most, 31 characters will be

              displayed. Strings longer than 31 character will be

              truncated to 30 characters and displayed with a trailing

              ellipsis.  Line feed characters are displayed as boxes.

           { fields }

              Is a list of the form { field1 field2 ... fieldn } where

              each field is any one of these forms:

                1.    "label"

                2.    { "label" "help" }

                3.    { "label" "help" type1 type2 ... typen }

                4.    { }

           The "label" is a string of arbitrary text from 0 to 26 char-

           acters long (longer strings will be truncated to 25 charac-

           ters with a trailing ellipsis).  The "help" is displayed

           immediately above the menu area as a helpful prompt for the

           user.  The object type specifications list the one or more

           object types allowed in the field, in the form the TYPE com-

           mand returns.  If unspecified, the default help text is blank

           and the field will accept all object types.  If a field spec-

           ification is an empty list, no field is produced; instead,

           the field to the immediate left (if any) is expanded to fill

           the omitted field's space.  This allows further customization

           of form layout; for example, to have two fields in one row

           and three fields in the next.

           <format>

              May be any one of the following objects:

                1.    { }

                2.    columns

                3.    { columns }

                4.    { columns widths }

           Where <columns> is the number of columns that the display

           will be divided into e.g., if <columns> is 2 and there are

           two fields, they will be displayed side by side rather than

           one above the other.  <widths> is the tab width between the

           left edge of each title and its field; this makes vertical

           alignment of fields possible.  Titles longer than one tab

           width will cause the tab to be repeated automatically.  If

           unspecified, the default column count is one and the default

           tab stop width is three.

           { reset_values }

              Is a list of values one per input field which replace the

              values of all fields when the {RESET} key is pressed and

              "Reset all" is selected.  This list must either be empty

              or have exactly one item per field corresponding to the {

              fields } list above.  If empty, then all fields are deemed

              unspecified (i.e., blank).  Each reset value must match

              the type require by the form field. Selected fields may be

              marked as unspecified by using NOVAL as the reset value.

           { initial_values }

              is a list of values one per input field which specify the

              start-up values of all fields when the INFORM command is

              invoked. This list must either be empty or have exactly

              one item per field corresponding to the { fields } list

              above.  If empty, then all fields are deemed unspecified

              (i.e., blank).  Each initial value must match the type

              require by the form field.  Selected fields may be marked

              as unspecified by using NOVAL as the initial value.

        RESULTS:

           INFORM returns the new field values { new_values } as a list

           to level 2 and the real value 1 to level 1 if the user

           completes the input form by pressing {OK} or ENTER.  The list

           will contain one item per field.  Each item will either be

           the last input value for the corresponding field, or NOVAL if

           the field was unspecified.

           INFORM returns the real value 0 to level 1 if the user

           terminates the input form by pressing {CANCL} or CANCEL.

        REMARKS:

           NOVAL is basically a command (an XLIB name) that does nothing

           when evaluated. It can, however, be compared via ==, SAME and

           POS.

     CHOOSE - Create a User-Defined Choose-Box

        INPUT:

             3: "title"

             2: { items }

             1: <initial_item_number>

        OUTPUT:

             Either: 2: { chosen_item }

                     1: 1

             or:     1: 0

        PURPOSE:

           CHOOSE creates a user-defined "choose-box": a displayed box

           containing items from which the user can choose one.

           CHOOSE displays a standard choose box (normal, not maximized;

           single-pick, not multi-pick) with an optional title line.

        ARGUMENTS:

           title

              If any, is displayed in font 1 (small) in the top centre

              of the box.  It may contain any number of characters,

              including 0, but, at most, 22 characters will be

              displayed. Strings longer than 22 character will be

              truncated to 21 characters and displayed with a trailing

              ellipsis.  Line feed characters are displayed as boxes.

              If there are more than four items such that the scroll

              arrows are displayed, the maximum number of title

              characters is reduced to 21.  The title text is displayed

              in the title area in character font 1 (the menu font).  If

              the title string is empty, no title area will be created

              in the choose box, and the whole box will be devoted to

              the items.

           { items }

              Is a list of arbitrary objects.  Each item occupies one

              line in the choose box and is displayed in its command

              line form.  Only the first 14 characters of the displayed

              object will be shown (13 if the scroll arrows are

              present).  If an item contains more than 14 (13)

              characters, it will be truncated to 13 (12) and the final

              character will be replaced by an ellipsis.  If every item

              is a list of exactly two objects, the first object will be

              displayed and the second returned if the item is selected.

              If the number of items exceeds 4 with a title and 5

              without, scroll arrows will be displayed, and moving the

              highlight past the top or bottom of the box will scroll

              through the undisplayed items.

           <initial_item_number>

              Specifies the initial field to be highlighted when the

              display first comes up (ordinarily 1).  A value of 0

              indicates that no field is to be highlighted and that the

              {CANCL} key is to be omitted from the menu, making the

              choose box act as an informational display without user

              selection.

        RESULTS:

           CHOOSE returns the chosen item (or the second object in a

           two-element item list) and the real number 1 if the user

           completes the choose box by pressing {OK} or ENTER.  CHOOSE

           returns the real number 0 if the user terminates the choose

           box by pressing {CANCL} or CANCEL.

     MSGBOX - Create a Simple Message Box

        INPUT:

             1: "Message_string"

        OUTPUT:

             None

        PURPOSE:

           MSGBOX creates a simple pop-up message box over the current

           display, with a 3D shadow to make it easy to recognize, and

           containing any arbitrary text.

        ARGUMENTS:

           Message_string

              Is any string of characters.  The text is displayed in

              font 2 (medium size), left justified, with a maximum line

              length of 15 characters.  Longer lines are broken into

              multiple lines automatically, at word breaks when

              possible, up to a maximum of 5 lines.  Line feeds may be

              included to force line breaks.  The minimum number of

              lines is 2, so single-line messages will have a blank line

              at the bottom of the box.

        RESULTS:

           None.  MSGBOX is exited when the user presses CANCEL, ENTER,

           or OK, but nothing is returned to the stack.

  For examples of INFORM, CHOOSE, and MSGBOX see Appendix B-2.


How do I put checkfields in my INFORM menus?

7.21.  How do I put checkfields in my INFORM menus?

  From: Matt Willis

  You can't normally do this directly in User RPL.  You can do it in

  System RPL (see Jim Donnelly's book for details), or you can use the

  library at  <ftp://ftp.cis.com/pub/hp48g/uploads/infm2v1.zip>

  I figured that the System RPL version of DoInputForm was unpleasant

  enough to use on a casual basis so I wrote a simple library that lets

  you use check boxes and choose lists from User RPL.

  All it does is stop execution of INFORM just before DoInputForm, then

  search the stack and change object types to check and choose objects.

  Then it restarts the INFORM command.  At the end, it tidies up

  TRUE/FALSE to 1/0 etc...

  Example syntax:

       "Test" {

       "A" "B" "C" } 1 {} { :CHECK: 1  :CHOOSE: { 1 2 3 }  NOVAL }

       IF INFORM2 THEN

          ...insert code here...

       END


Appendix A: Various Useful Functions

8. Appendix A: Various Useful Functions

8.1 ASC Functions

8.2 OBJFIX

8.3 FIXIT

8.4 LASTX

8.5 Compact Data Storage


ASC Functions

  8.1.  ASC Functions

  Note: Although this document mentions SX only, ASC\-> and \->ASC work

           on both the SX and GX.

  From: Bill Wickes

  ASCII Encoding HP48 SX Objects

  Sending an HP48 SX object via electronic mail can be difficult if the

  object does not have an ASCII form, such as is the case for library

  objects.  There are various encoding schemes available on different

  computer systems, but these require that the sender and receiver have

  similar computers, or at least compatible encode/decode schemes.  The

  programs listed below perform the encoding and decoding on the HP48 SX

  itself, which has the advantage of being completely independent of any

  computer.

  The programs are nominally called \->ASC and ASC\->.  The former takes

  an object from the stack and converts it to a string, in which each

  nibble of the object and its checksum is converted to a character 0-9

  or A-F.  (The object must be in RAM, otherwise a "ROM Object" error is

  returned.)  For sake of easy inclusion in email letters, the string is

  broken up by linefeed characters after every 64 characters.

  ASC\-> is the inverse of \->ASC: it takes a string created by \->ASC

  and converts it back into an object.  When you transmit the encoded

  strings, be sure not to change the string; ASC\-> uses the checksum

  encoded in the string to verify that the decoding is correct.  An

  "Invalid String" error is returned if the result object does not match

  the original object encoded by \->ASC.  When you upload a string to

  your computer, use HP48 translate mode 3 so that the HP48 will convert

  any CR/LF's back to LF's when the string is later downloaded.

  Two versions of ASC\-> are included here.  The first (P1) is in HP48

  user language, using SYSEVALs to execute system objects.  P2 is a

  string that the setup program uses P1 to decode into an executable

  ASC\-> - then P1 is discarded.  The second version is more compact

  than the first, and also uneditable and therefore safer (but it can't

  be transmitted in ASCII form, which helps to make the point of this

  exercise).

  Here are the programs, contained in a directory:

  %%HP: T(3)A(D)F(.);

  DIR

  P1              @ ASC\-> Version 1.

  \<<

    IF DUP TYPE 2 \=/

    THEN "Not A String" DOERR

    END RCWS \-> ws

    \<< 16 STWS

      #0 NEWOB SWAP DUP SIZE

      IF DUP 4 <

      THEN DROP SWAP DROP "Invalid String" DOERR

      END

      DUP 65 / IP - 4 - # 18CEAh SYSEVAL

      "" OVER # 61C1Ch SYSEVAL

      SWAP # 6641F8000AF02DCCh

      # 130480679BF8CC0h # 518Ah SYSEVAL

      # 19610313418D7EA4h # 518Ah SYSEVAL

      # 7134147114103123h # 518Ah SYSEVAL

      # 5F6A971131607414h # 518Ah SYSEVAL

      # 12EA1717EA3F130Ch # 518Ah SYSEVAL

      # 280826B3012808F4h # 518Ah SYSEVAL

      # 6B7028080BEE9091h # 518Ah SYSEVAL

      # BE5DC1710610C512h # 518Ah SYSEVAL

      # 705D00003431A078h # 518Ah SYSEVAL

      # 3D8FA26058961431h # 518Ah SYSEVAL

      # 312B0514h # 518Ah SYSEVAL

      # 18F23h SYSEVAL

      DUP BYTES DROP 4 ROLL

      IF ==

      THEN SWAP DROP

      ELSE DROP "Invalid String" DOERR

      END ws STWS

    \>>

  \>>

  P2      @ ASC\->  Version 2.  To be converted by ASC\-> version 1.

  "D9D20D29512BF81D0040D9D20E4A209000000007566074726636508813011920

  140007FE30B9F060ED3071040CA1304EC3039916D9D2085230B9F06C2A201200

  094E66716C696460235472796E676933A1B21300ED30FD5502C230C1C1632230

  CCD20FA0008F14660CC8FB97608403104AE7D814313016913213014117414317

  414706131179A6F5C031F3AE7171AE214F8082103B6280821909EEB0808207B6

  215C0160171CD5EB870A13430000D50713416985062AF8D341508813044950B9

  F06BBF06EFC36B9F0644230C2A201200094E66716C696460235472796E676933

  A1B2130B21300373"

  P3      @\->ASC.     To be converted by ASC\->.

  "D9D20D2951881304495032230FD5502C230A752688130ADB467FE30322306AC3

  0CB916E0E30CBD30F6E30C1C1632230CCD20DC0008F14660CC8FB97608403104

  AE7D8143130169174147061741431311534AC6B4415141534946908D9B026155

  4A6F53131F3AE731A014C161AE215F08082103A6280821939EEC08082170A621

  4C161170CD56B870A18503430000D5071351796A9F8D2D02639916D9D2085230

  C2A209100025F4D402F426A6563647933A1B2130A2116B213033C0"

  SETUP   @Automatic setup program

  \<< P2 P1 'ASC\->' STO

      P3 ASC\-> '\->ASC' STO

      { P1 P2 P3 SETUP } PURGE

  \>>

  END

  Installation instructions:

  1. Edit the above text between (start) and (end) into a text file

     named CONV (for example).  Be sure that you leave the strings

     exactly as entered above, with no extra spaces or other invisible

     characters at the beginnings or ends of the lines.

  2. Set the HP48 SX into ASCII transfer mode.

  3. Using Kermit, download CONV text file to the 48, verify its

     checksum (6C8Ah).

  4. Execute CONV to make it the current directory.

  5. Execute SETUP.

  6. The directory CONV now contains ASC\-> and \->ASC, ready to use.

  To archive the decoded versions of ASC\-> and \->ASC back on your

  computer, be sure to set the HP48 SX in binary transfer mode before

  uploading.

  Disclaimers:

  •  Use the programs at your own risk.  Any time you delve into the

      SYSEVAL world, there are increased dangers.  Archive your 48 memory

      before experimenting with these programs!  Also, verify the

      checksums of objects defined above to make sure they have been

      downloaded correctly, before executing ASC\->.

  •  I will not answer questions about how the programs work.  This is

      not because of any great secrecy, but rather because it's hard to

      give any answer that doesn't lead to more questions, and more, and

      more...

  •  48 hackers are welcome to mine any nuggets they can from the

      programs, and from the fact that \->ASC is a convenient way to

      decompile an object.


OBJFIX

  8.2.  OBJFIX

  When a binary object received by Kermit on the HP-48 is left as a

  string beginning with HPHP48, OBJFIX will extract the HP-48 object if

  the only problem is that extra bytes got appended to the end.

  OBJFIX takes a variable name in stack level 1 and modifies the

  contents of the variable if no other problems are detected.

  Note: This is like FIXIT by Horn and Heiskanen on Goodies Disk 8, but

           this one is by HP and so I suppose it's more reliable.  Although it

           fails the test cases included with FIXIT, that may be because they

           were artificially contrived cases.  Try both on real-world downloads

           that need fixing.  Which do you like better?

  OBJFIX.ASC

    %%HP: T(3)A(D)F(.);

    "D9D202BA81D9F81B2040D9D20F2A26DA91629C8145126489162C23072C80CCD2

    0BD0008FB9760147108134164142C2818F24D534501008B2F41643150D73B840

    58405438314A161966D2BF6BF6A6F5BE16314213114334CF8208A6F58F235A04

    55136D7D4EA494D231A1CA101110131CA130DBE284F8FC0760D41198F29960D4

    130142119EA1408F5E0108D341503223072D70B2130B21301460"


FIXIT

  8.3.  FIXIT

  From: Joe Horn and Mika Heiskanen

     PURPOSE:

        Converts a badly uploaded string into the original object.

     THEORY:

        A lot of folks upload HP48 objects poorly, such that when you

        download them, you just get strings full of garbage that look

        something like this:

          "HPHP48-E#c&r$a%p@!*!..."     [looks familiar, eh?]

     That's because they uploaded it using XMODEM, or managed to screw

     it up some other way.  The following FIXIT program takes such a

     string and extracts the actual HP48 object that they originally

     intended to upload (if at all possible).

     Such object extraction can be done by hand, but it's too dangerous.

     FIXIT minimizes the danger of Memory Clear.  It checks whether the

     extracted object is a valid one, and if not, drops it from the

     stack before the HP48 attempts to display it.  All of the many bad

     downloads I've archived over the years are fixed by FIXIT, whereas

     about half of them cause a Memory Clear when extracted manually.

     No guarantees, however.  Use at your own risk.

     The actual extraction is done by a "Code object" written by Mika

     Heiskanen.  The User RPL "shell" around this code object is what

     minimizes the danger of Memory Clear; it was written by Joe Horn.

     INSTRUCTIONS:

        BACKUP YOUR MEMORY, just in case the string contains a logic

        bomb.

        Place the bad download on the stack (see "HPHP48-...") and run

        FIXIT.

        Possible results:

     •  No error: the object was extracted successfully and is on level 1.

     •  "Bad Argument Type" error: you didn't have a string on level 1.

     •  "Bad Argument Value" error: the string wasn't of the proper

         form; it must be an "HPHP48-..." downloaded string.

     •  "Invalid Definition" error: the object was mangled in

         transmission so badly that its end was lost; the object cannot

         be extracted.

     •  "Undefined Result" error: there is no HP48 object in the string.

     •  "Recover Memory? YES/NO": the string contained a bomb, and FIXIT

         detonated it.  Press YES to sift through the shrapnel and rubble

         in a feeble attempt to resurrect the dead.  Press NO to bury

         them.

     EXAMPLES:

        To do the following examples, download the FIXIT directory to

        your HP48 and get into it.

     •  Press HI.  See "HPHP48-E...", a badly uploaded download.  Before

         pressing FIXIT to fix it, try doing what we all used to do:

         press EDIT to see if we can recognize anything (usually a futile

         attempt).  We see:

         "HPHP48-E...  << Melancholy Baby >>"

         But looks can be deceiving; press ON to exit the editor, and

         then press FIXIT to extract the intended upload:

         << Happy Camper >>

     •  Press WTAV; see another garbage download.  But EDIT refuses; the

         string contains null characters.  Press FIXIT; see successfully

         extracted directory.

     •  Press BAD1.  Notice that it looks exactly like WTAV.  (Press

         WTAV, compare, then DROP).  But its ending is all messed up;

         manually extracting WTAV from BAD1 can cause Memory Clear.

         Press FIXIT and see "Error: Invalid Definition" indicating that

         the object inside BAD1 is so mangled that its end cannot be

         located.

     •  Press BAD2.  Looks like WTAV again.  But its body is messed up;

         manually extracting it would create an External object that

         could cause Memory Clear if evaluated.  Press FIXIT and see

         "Error: Undefined Result" indicating that there is nothing

         recognizable inside BAD2.

  FIXIT.ASC

    %%HP: T(3)A(D)F(.);

    "69A20FF7CE20000000402414442340C2A203B000840584054383D25403A20FF7

    2500000000403535947440D9D20E16329C2A2DBBF13013216DF1406A1C42328D

    BF193632B213034000407545146540D9D20E163292CF1EFFB1DBBF1EBFB150FA

    193632B2130003030303034C000402414441340C2A203B000840584054383D25

    469A20FF72500000000403535947440D9D20E16329C2A2DBBF13013216DF1406

    A1C42328DBF193632B213034000407545146540D9D20E163292CF1EFFB1DBBF1

    EBFB150FA193632B2131313131313134C000407545146540C2A203B000840584

    054383D25469A20FF72500000000403535947440D9D20E16329C2A2DBBF13013

    216DF1406A1C42328DBF193632B213034000407545146540D9D20E163292CF1E

    FFB1DBBF1EBFB150FA193632B2130003030303034C00020849420C2A20570008

    40584054383D254D9D20E163284E2050841607079784E20603416D6075627936

    32B2130A0BA02D456C616E63686F6C697022416269702BB28000506494859445

    50D9D20E16323CE2278BF168BC1ED2A2167E1AFE22D9D203CE2278BF19C2A274

    3A2C58C1C2A2031000840584054383D2167E1AFE22D9D2078BF18B9C1DBBF1AA

    F028DBF1CCD201200014713717917F137145142164808C5BF22D9D2033920200

    0000000005150933A1B21305DF22B21305BF22D9D20339202000000000004150

    933A1B21305DF223CE2278BF168BC1D8DC1167E1AFE22D9D203FBF1339202000

    000000002770933A1B21305DF223CE2278BF19D1A1DBBF18DBF1E0CF1D5CE1AF

    E22D9D208DBF1339202000000000000030933A1B21305DF22CB2A193632B2130

    B21303D4F"


LASTX

  8.4.  LASTX

  The LASTX function is useful in calculations where a number occurs

  more than once.  By recovering a number using LASTX, you do not have

  to key that number into the calculator again.  Note however that LASTX

  uses the built in last argument feature, so if you use LASTX you will

  lose the contents of your LASTARG.

  For example, calculate:

         96.704 + 52.394706

        --------------------------------

             52.394706

Keystrokes:	Stack:
96.704 ENTER	96.704
52.304706 +	149.098706
LASTX	149.098706 52.304706
/	2.84568265351

    @ This is a version of LASTX for the HP48

    @

    %%HP: T(3)A(D)F(.);

    \<< DEPTH \-> n

      \<< LASTARG DEPTH n

    - DUP \-> s

        \<< ROLLD s 1 -

    DROPN

        \>>

      \>>

    \>>


Compact Data Storage

  8.5.  Compact Data Storage

  From: Jim Donnelly

  A simple length-encoding technique can be put to use for a free-

  format, very compact multi-field data storage system.  Two tiny

  programs, SUBNUM and STRCON are here to help the process, and are

  listed near the end of this note.  At the end of the note is a

  directory that may be downloaded into the HP48 that contains the

  examples.

  The principle is to store starting indices in the beginning of a

  string that point to fields stored subsequently in the string.  The

  indices are stored in field order, with an additional index at the end

  to accommodate the last field.  There are several small points worth

  mentioning:

  •  Fields may be 0-length using this technique.

  •  The execution time is uniform across all fields.

  •  This technique saves about 4 bytes per field after the first field,

      because the string prologue and length are omitted for fields 2 -> n.

     EXAMPLE:

                  Indices  |          Fields

   Character               |     1 11111111 12222222222

   Position :   1  2  3  4 |567890 12345678 90123456789

               +--+--+--+--+------+--------+-----------+

   String :    | 5|11|19|30|Field1| Field2 |  Field 3  |

               +--+--+--+--+------+--------+-----------+

     This is a string that contains 3 fields, and therefore 4 index

     entries.  The first field begins at character 5, the second field

     begins at character 11, and the third field begins at character 19.

     To keep the pattern consistent, notice that the index for field 4

     is 30, which is one more than the length of the 29 character data

     string.

     To extract the second field, place the string on the stack, use

     SUBNUM on character 2 to extract the starting position, use SUBNUM

     on character 3 to extract the (ending position +1), subtract 1 from

     the (ending position+1), then do a SUB to get the field data.

     NOTE: The index for field 1 is stored as char. data 5, NOT the

     string "5"!  To place the field index for field 1 in the string,

     you would execute "data" 1 5 CHR REPL.

     PROGRAM:

        The following program accepts an encoded data string in level 2

        and a field number in level 1:

     DECODE   "data"  field#  -->  "field"

     <<  --> f

       <<

         DUP f SUBNUM                ; "data" start -->

         OVER f 1 + SUBNUM           ; "data" start end+1 -->

         1 -                         ; "data" start end -->

         SUB                         ; "field" -->

       >>

          >>

     DATA ENCODING:

        The following program expects a series of 'n' strings on the

        stack and encodes them into a data string suitable for reading

        by the first example above.

        The programs SUBNUM and STRCON are used to assemble the indices.

     ENCODE      field n  ...  field 1   n   -->  "data"

     << DUP 2 + DUP 1 - STRCON --> n  data

       <<

         1 n

         FOR i

           data i SUBNUM OVER SIZE   ; ... field index fieldsize

           + data SWAP               ; ... field "data" index'

           i 1 + i + SWAP CHR REPL   ; ... field "data"'

           SWAP + 'data' STO         ; ...

         NEXT

         data                        ; "data"

       >>

     >>

     In this example, four strings are encoded:

     Input:  5: "String"

                4: "Str"

                3: "STR"

                2: "STRING"

                1:         4

     Output: "xxxxxSTRINGSTRStrString"

                  (23 character string)

                  (The first five characters have codes 6, 12, 15, 18, and 24)

     VARIATION:

        The technique above has a practical limit of storing up to 254

        characters of data in a string.  To overcome this, just allocate

        two bytes for each field position.  The code to extract the

        starting index for becomes a little more busy.  In this case,

        the index is stored as two characters in hex.

                  Indices  |          Fields

   Character               | 11111 11111222 22222223333

   Position :   12 34 56 78|901234 56789012 34567890123

               +--+--+--+--+------+--------+-----------+

   String :    |09|0F|17|21|Field1| Field2 |  Field 3  |

               +--+--+--+--+------+--------+-----------+

     <<  --> f

       <<

          DUP f 2 * 1 -           ; "data" "data" indx1 -->

          SUBNUM 16 *             ; "data" 16*start_left_byte  -->

          OVER f 2 * SUBNUM +     ; "data" start

          OVER f 2 * 1 + SUBNUM   ; "data" start end_left_byte -->

          16 * 3PICK f 1 + 2 *

          SUBNUM + 1 -            ; "data" start end -->

          SUB                     ; "field"  -->

       >>

     >>

     TWO VERY TINY HELPFUL PROGRAMS:

          SUBNUM          "string"  position  -->  code

     << DUP SUB NUM >>

          STRCON          code  count  -->  "repeated string"

     << -->  code count

       << "" code CHR 'code' STO

          1 count START code + NEXT

       >>

     >>

     Alternative Solution to the Problem:

        From: Matjaz Vencelj <vencelj@fmf.uni-lj.si>

        Jim allocates two bytes for each index entry (to handle longer

        strings), but on the other side obviously only uses values

        00...FF for index dublets, which just doesn't make sense.  He's

        at a 16*16 = 255 chars limit again!

        I have put together a working set of commands which support up

        to 65K strings, using two-byte indexing.

        The encoder (Encode) is User-RPL program which calls the binary

        N2C which converts the level 1 real into a 2 character string:

      @*** Encode ***

      %%HP: T(3)A(R)F(.);

      \<<

        IF DUP TYPE 0 = THEN 514 DOERR END

        \-> N

          \<<

          N 1 + 2 * #18CEAh SYSEVAL #45676h SYSEVAL

          1 N FOR I I 2 * 1 - OVER SIZE 1 + N2C REPL SWAP + NEXT

          N 2 * 1 + OVER SIZE 1 + N2C REPL

          \>>

      \>>

      @*** N2C, cksum=#8919h ***

      %%HP: T(3)A(R)F(.);

      "D9D202BA812BF819FF30D9D20AEC8111920001007FE3057A50C57463223057A5

      0EE250B2130B21307206"

     ASCII download them with translate code 3, then call program

     'Encode' with data strings in levels 2..n+1 and a real n in level 1

     indicating the number of strings.

     The string decoder (Decode), which is usually speed-critical, is

     the following \->ASC encoded binary:

      @*** Decode, cksum=#38E1h ***

      %%HP: T(3)A(R)F(.);

      "D9D20D8A81D9F811192013000D9D20AEC8113D26CA130F6E30CA130E0E305080

      311920001002CE30CAF0650803CBD30CAF06FED30F6E30CA130E0E3050803119

      20001002CE30CAF0650803CBD30E0E3033750B2130B21309534"

     It takes a `database' string on level 2 and a real (record position) on level 1,

     then comes back with the appropriate substring (record).


Appendix B: GX Specific Information

9. Appendix B: GX Specific Information

9.1 What's new in the HP48 G/GX?

9.2 Examples of INFORM, CHOOSE, and MSGBOX

9.3 Some useful LIBEVALs


What's new in the HP48 G/GX?

  9.1.  What's new in the HP48 G/GX?

  From: Joe Horn

     1.   Automatic Processing

     2.   Ports and Memory

     3.   Local Variables

     4.   Speed

     5.   Improved Commands

     6.   HP solve Equation Library Card Commands

     7.   New Array Commands

     8.   Graphics and Plotting Commands

     9.   User-Interface Commands

     10. List Processing Commands

     11. System Commands

     12. Math Commands

     13. Menu Numbers and Key Codes

     14. Manuals

     15. Flags

     16. Flag Browser

     17. Character Browser

     18. Directory Maintenance

     19. Fractional Unit Powers

     20. Name Plate

     21. XLIB Names

     22. Input Forms and Choose Boxes

     23. Enchanced Precision

     24. Improved Display


Automatic List Processing

    9.1.1. Automatic List Processing

    Almost all commands that did not accept list(s) as their

    arguments can do so now.  Here are just a few examples:

      { 1 2 3 } SF sets flags 1, 2, and 3

      { 1 2 3 } SQ  -->  { 1 4 9 }

      { 2 4 } 10 /  -->  { .2 .4 }

      10 { 2 4 } /  -->  { 5 2.5 }

      { 10 12 } { 2 4 } /  -->  { 5 3 }

      { .1 .2 .5 } ->Q  -->  { '1/10' '1/5' '1/2' }

      { freq freq ...} { dur dur ... } BEEP can play a song with no

        audible hiccup between tones.

    Since + has always been used to concatenate lists, a new ADD function

    exists to add the elements of two lists, like this:

      { 1 2 3 } { 4 5 6 } ADD returns { 5 7 9 }, whereas

      { 1 2 3 } { 4 5 6 }  +  returns { 1 2 3 4 5 6 } as it did

        before.

    The only commands which do not have automatic list processing are:

    •  those which never get a Bad Argument Type error (like DUP),

    •  meta-object commands (like ROLL),

    •  program branch structures (like FOR), and

    •  commands that specifically work on lists (like GET).

        Sometimes the results are non-obvious, for example:

      5  { A B C }  STO           -->  A=5, B=5, C=5

      { 5 6 7 }  'A'  STO         -->  A={ 5 6 7 }  (same as on SX)

      { 5 6 7 }  { A B C }  STO   -->  A=5, B=6, C=7

    List processing is only recursive for ->Q and ->Qpi.


Ports and Memory

    9.1.2. Ports and Memory

    The HP48 G, like the 48 S, only has 32K RAM.  The GX, unlike the

    SX, has 128K RAM built-in.  Card slot 1 can contain another 128K

    (maximum), but card slot 2 can contain up to 4 megabytes of RAM.

    Only port 1 can be merged in the GX.  Card slot 2, which is

    intended for large-capacity RAM cards, is permanently "free",

    and is automatically divided up into 128K "ports", each of which

    becomes Port 2, Port 3, Port 4, etc.  Up to 4 Megabytes can be

    plugged into slot 2, which would then become Port 2 through Port

    33. (Although the FREE and MERGE commands were kept for HP48 SX

    compatibility, GX users will prefer the new FREE1 and MERGE1

    commands).  Therefore the maximum amount of merged main memory

    is 256K (unlike the SX which allowed up to 288K) after MERGE1;

    the maximum amount of fully online free independent memory is

    4224K after FREE1.


Local Variables

    9.1.3. Local Variables

    Variable names prefixed with a <- (backarrow character) are

    compiled as local (temporary) variable name objects even if

    they're not explicitly after FOR or ->.  This allows programs to

    share values through local variables, which is much faster than

    sharing values through global variables, and they get purged

    automatically.


Speed

    9.1.4. Speed

    CPU clock speed is double the S/SX's, but throughput is

    estimated to be only 40% faster, primarily due to the fact that

    all RAM & ROM is now bankswitched (on the S/SX only a 32K

    portion of the ROM required bank switching), and it still has

    the same 4-bit bus bottleneck.


Improved Commands

    9.1.5. Improved Commands

    •  AXES can now also specify the spacing of the tick marks.

    •  DEPND can now also specify the initial values and tolerance for

        the new DIFFEQ plot type.

    •  REPL and SUB now work on arrays.


HP solve equation library card commands

    9.1.6. HP solve equation library card commands

    •  AMORT, amortization calculations

    •  CONLIB, starts Constants Library catalog

    •  CONST, returns value of a named CONLIB constant

    •  DARCY, calculates Darcy friction factor

    •  EQNLIB, starts Equation Library catalog

    •  F0lambda, calculates black-body power fraction

    •  FANNING, calculates Fanning friction factor

    •  LIBEVAL is a generalized form of the EQ card's ELSYSEVAL; it

        executes any XLIB by its library number

    •  MCALC, marks an MSOLVR variable as "not user-defined"

    •  MINEHUNT, starts the "Minehunt" video game

    •  MINIT, initializes Mpar from 'EQ' for MSOLVR

    •  MITM, customizes title & menu of MSOLVR's screen

    •  MROOT, solve for variable(s) in MSOLVR

    •  MSOLVR, shows Multiple Equation Solver menu

    •  MUSER, marks an MSOLVR variable as "user-defined"

    •  SIDENS, density of silicon as function of temperature

    •  SOLVEQN, starts solver for specified EqLib equation(s)

    •  TDELTA, subtracts temperatures like "-" ought to but doesn't

    •  TINC, adds temperatures like "+" ought to but doesn't

    •  TVM, shows the financial calculator (Time Value of Money) menu

    •  TVMBEG, sets payments-at-beginning-of-periods mode

    •  TVMEND, sets payments-at-end-of-periods mode

    •  TVMROOT, solves for a TVM variable

    •  ZFACTOR, calculates gas compressibility factor Z

    Note: The EQ Card's Periodic Table and Tetris game are not in

              the HP48 G/GX, but the EQ Card can be used in the GX if those

              applications are needed. Tetris was not included because no

              agreement on royalty was reached.  The Periodic Table is

              available separately as freeware on HPCVBBS.


New array commands

    9.1.7. New array commands

    •  COL+, inserts a column vector into a matrix or a number into a

        vector (like INSCOL/PUTCOL in Donnelly's Tool Library)

    •  COL-, deletes a column from a matrix or number from a vector

        (identical to DELCOL in Donnelly's Tool Library)

    •  COL->, combines multiple column vectors into a matrix

    •  ->COL, breaks a matrix into multiple column vectors (like

        repeated GETCOL in Donnelly's Tool Library)

    •  COND, column norm condition number of a square matrix

    •  CSWP, swaps two columns in a matrix (like EXCOL in Donnelly's

        Tool Library)

    •  ->DIAG, returns vector of major diagonal elements of a matrix

    •  DIAG->, creates matrix with specified diagonal elements

    •  EGV, eigenvalues and right eigenvectors of a square matrix

    •  EGVL, eigenvalues of a square matrix

    •  FFT, discrete Fourier transform

    •  IFFT, inverse discrete Fourier transform

    •  LQ, returns the LQ factorization of a matrix

    •  LSQ, minimum norm least-squares solution to an ill-determined

        system of linear equations

    •  LU, returns the Crout LU decomposition of a square matrix

    •  PCOEF, returns polynomial with given roots (inverse of PROOT)

    •  PEVAL, evaluates polynomial at x

    •  PROOT, finds all roots of polynomial (inverse of PCOEF)

    •  QR, returns QR factorization of a matrix

    •  RANK, rank of a rectangular matrix (uses flag -54)

    •  RANM, creates matrix with random elements

    •  RCI, multiplies elements in one row of a matrix by a scalar

    •  RCIJ, does RCI then adds the result to a row

    • ROW+, inserts a row vector into a matrix or a number into a

        vector (like INSROW/PUTROW in Donnelly's Tool Library)

    •  ROW-, deletes a row from a matrix or number from a vector

        (identical to DELROW in Donnelly's Tool Library)

    •  ROW->, combines multiple row vectors into a matrix

    •  ->ROW, breaks a matrix into multiple row vectors (like repeated

        GETROW in Donnelly's Tool Library)

    •  RSWP, swaps two rows in a matrix (identical to EXROW in

        Donnelly's Tool Library)

    •  SCHUR, computes the Schur decomposition of a square matrix

    •  SNRM, spectral norm of an array

    •  SRAD, spectral radius of a square matrix

    •  SVD, singular value decomposition of a matrix

    •  SVL, computes the singular values of a matrix

    •  TRACE, sum of diagonal elements of a square matrix


Graphics and Plotting Commands:

    9.1.8. Graphics and Plotting Commands:

    •  ANIMATE, displays grobs on the stack sequentially.  You can use

        the defaults, or specify your own delay between frames (can be

        very fast), the number of times to repeat the sequence, and even

        the pixel coordinates.  It's just like a ROLL REPL loop...

        except very fast.  Note: Charlie Patton converted 17 seconds of

        the Apollo moon-walk video into HP48 GROBs and ran them with

        ANIMATE, and it looked very good!

    •  ATICK, specifies tick spacing on plot axes

    •  EYEPT, specifies the eye-point coordinates in a perspective plot

    •  GRIDMAP, selects the new "gridmap" plot type

    •  PARSURFACE, selects the new "parametric surface" plot type

    •  PCONTOUR, selects the new "pcontour" plot type

    •  PICTURE, same as GRAPH command

    •  SLOPEFIELD, selects the new "slopefield" plot type

    •  WIREFRAME, selects the new "wireframe" plot type

    •  XVOL, sets the width of the 3D plotting volume

    •  XXRNG, sets the width of the 3D target mapping range for gridmap

        and parametric surface plots

    •  YSLICE, selects the new "yslice" plot type

    •  YVOL, sets the depth of the 3D plotting volume

    •  YYRNG, sets the depth of the 3D target mapping range for gridmap

        and parametric surface plots

    •  ZVOL, sets the height of the 3D plotting volume


User-Interface Commands

    9.1.9. User-Interface Commands

    •  CHOOSE, displays a point-and-click menu "dialog box"

    •  INFORM, formatted multi-line input with named fields (nice!!)

    •  MSGBOX, displays text in a centred box with shadow, then WAITs

    •  NOVAL, placeholder for unspecified values in INFORM argument

        list


List Processing Commands

    9.1.10. List Processing Commands

    •  ADD, adds lists element-wise (see section above)

    •  DOLIST, evals an object on multiple lists

    •  DOSUBS, evals a program or command taking arguments from a list

    •  ENDSUBS, returns the number of loops the current DOSUBS will do

    •  HEAD, first element in a list or first char in a string

        (identical to CAR in Donnelly's Tool Library)

    •  DeltaLIST, list of first finite differences of list objects

    •  SigmaLIST, sum of the elements in a list

    •  PiLIST, product of the elements in a list

    •  NSUB, returns the current list pointer value during a DOSUBS

    •  REVLIST, reverses the order of the objects in a list (like

        REVERSE in Donnelly's Tool Library)

    •  SEQ, list of results from repeated execution of an object (like

        a FOR/STEP loop but the results go into a list)

    •  SORT, sorts elements in a list into ascending order, or sorts a

        list of lists using each list's first element as the key (can be

        done with LSORT/QSORT in Donnelly's Tool Library)

    •  STREAM, executes an object on first two elements of a list, then

        again on the result and the 3rd element, etc.  Allows easy

        creation of things similar to SigmaLIST and PiList.

    •  TAIL, returns a decapitated list or string (see HEAD above)

        (identical to CDR in Donnelly's Tool Library)


System Commands

    9.1.11. System Commands

    •  CLTEACH, clears the 'EXAMPLES' directory created by TEACH

    •  CYLIN, sets polar/cylindrical coordinate mode

    •  FREE1, like 1 FREE (see section above)

    •  MERGE1, like 1 MERGE (see section above)

    •  PINIT, port initialize, esp. important for 4-Meg RAM card users

    •  RECT, sets rectangular coordinate mode

    •  SPHERE, sets polar/spherical coordinate mode

    •  TEACH, loads the Owner's Manual examples into a dir in HOME

    •  VERSION, returns the operating system ROM version string and a

        copyright notice, like this:

        2: "Version HP48-R"      <-- means version "R"

        1: "Copyright HP 1993"

    •  XRECV, X-Modem protocol receive (binary mode only)

    •  XSEND, X-Modem protocol send (binary mode only)


Math Commands

    9.1.12. Math Commands

    •  LININ, tests whether an equation is linear in a given variable

    •  NDIST, normal probability density

    •  PCOV, population covariance of SigmaDAT

    •  PSDEV, population standard deviation of SigmaDAT

    •  PVAR, population variance of SigmaDAT

    •  RKF, solves initial value problem using Runge-Kutta-Fehlberg

    •  RKFERR, change in solution and absolute error using RKF

    •  RKFSTEP, next solution step with given error tolerance using RKF

    •  RRK, solves initial value problem using Rosenbrock & RKF

    •  RRKSTEP, next solution step with given error tolerance using RRK

    •  RSBERR, change in solution and absolute error using Rosenbrock


Menu Numbers and Key Codes

    9.1.13. Menu Numbers and Key Codes

    Many menu numbers have changed, so software that uses # MENU or

    # TMENU may not work the same as in the HP48 S/SX.

    (Specifically, only menu numbers 0-3, 28, 30, and 42-59 are the

    same). Likewise, almost all of the shifted keycodes correspond

    to new commands and menus, which programmers must take into

    account; for example, the "RAD" key on the S/SX had the keycode

    82.2, but it's 21.2 on the G/GX.  The left-shift key, which was

    orange on the S/SX, is now purple officially "lavender", and the

    right-shift key which was blue on the S/SX is now green

    officially "teal" on the G/GX.  Also, the digit-key menus can be

    activated by both shift keys; left-shift gives the softkey menus

    like in the S/SX, but the right-shift gives the new user-

    friendly full-screen menus.  The unshifted keys remain identical

    to the S/SX, except for a cosmetic colour change to match the

    very dark green of the calculator case.


Manuals

    9.1.14. Manuals

    The G/GX comes with two manuals, a "Quick Start Guide" for

    beginners, and a cost-cutting, slimmer owner's manual called the

    "User's Guide" which has only 21 pages about programming, since

    HP figures that the huge majority of all 48 owners never program

    it anyway.  The power users can buy the optional "Advanced Users

    Reference Manual" (similar to the S/SX's "Programmer's Reference

    Manual") which covers programming and the many commands that are

    not mentioned in the User's Guide.  There is no "Quick Reference

    Guide" like the S/SX came with, although the case still has a

    pocket for one.

    Jim Donnelly has marketed a nice pocket guide, but it's too wide

    to fit in the case's pocket.  The User's Guide is not spiral

    bound, but is made to open fully and last a long time, since

    it's not just glued but has sewn signatures like real books, and

    is printed on quality paper.

    Another possibility is "The HP 48G/GX Pocket Guide" by Chris

    Coffin and Thomas Dick (Grapevine Publications) from EduCALC.

    It's 80 pages long, contains a complete command reference (with

    input/output stack diagrams), alpha keyboard description, system

    flag description, as well as examples of how to use various

    calculator features.  This guide is designed to fit nicely in

    the pocket of the HP case.


Flags

    9.1.15. Flags

    Some previously "unused" flags are now used.  They are:

-14 Clear	= end-of-period payment mode (for TVM calculations)
Set	= beginning-of-period payment mode
-27 Clear	= display symbolic complex numbers in coordinate form    e.g. '(X,Y)'
Set	= display symbolic complex numbers using 'i'    e.g. 'X+Y*i'
-28 Clear	= plot multiple equations like the S/SX does (serially)
Set	= plot multiple equations simultaneously
-29 Clear	= include axes in plots (like the S/SX does)
Set	= omit axes from 2D and statistics plots
   -30 is no longer used (it never did anything useful anyhow)

-54 Clear	= tiny matrix elements get rounded to zero
Set	= leaves matrix elements alone

     The default setting of all these flags is Clear (as in the S/SX).


Flag Browser

    9.1.16. Flag Browser

    There is a System Flag browser which shows the flag number,

    shows whether it's set or clear, lets you toggle it, and shows

    in English what the current setting means.


Character Browser

     9.1.17. Character Browser

    While programming, if you want to type any character at all,

    press CHARS and a screenful of ASCII characters is displayed

    that you can browse with the arrow keys, and not only does the

    screen also show the ASCII code (NUM value) and even the

    shortcut keyboard key sequence (if any) for each character, but

    if you press ECHO, it will be "typed" into your program.

    There's no need any more for the alpha keyboard table.


     9.1.18. Directory Maintenance

    Press right-shift VAR to launch a Variable Browser which is a

    complete memory manager.  You can tag multiple objects and copy,

    move, or delete them all with a single keystroke; there's even a

    Mark All and an Unmark All, like a real computer.  It's slow,

    however, and has been obsoleted by the very fast PCT library.


Fractional Unit Powers

    9.1.19. Fractional Unit Powers

    The S/SX only handled integer powers of units correctly, but the

    G/GX can use any real number as a unit power.


Name Plate

    9.1.20. Name Plate

    The case has a rectangular indentation in the back like the HP

    95LX and 100LX, and it comes with an adhesive metal nameplate

    that you can get engraved with your name.  ($5 at EduCalc if

    ordered at time of purchase).


XLIB Names

    9.1.21. XLIB Names

    All of the new commands in the GX are XLIB names, and therefore

    take 5.5 bytes in programs.  The commands common to the SX and

    GX take 2.5 bytes each, as they did in the SX.


Input Forms and Choose Boxes/Enchanced Precision/Improved Display

    9.1.22. Input Forms and Choose Boxes

    Many operations have two menu types: the old SX style, and a new

    "drop-down" menu and "input forms" that have the feel of

    computer dialog boxes.  Especially useful for the HP48 beginner.


    9.1.23. Enchanced Precision

    The internal precision of at least some of the matrix routines

    has been improved; INV gets better answers on square matrices

    than the SX did.  HP has not released information about which

    routines were improved, how, and by how much.


    9.1.24. Improved Display

    The LCD introduced with revision M of the G/GX is easier to read

    since it has higher contrast between on/off pixels.  It has a

    slower cycle response time, however, making it difficult to use

    for rapid-motion video games or any other rapid animation.


Examples of INFORM, CHOOSE, and MSGBOX

  9.2.  Examples of INFORM, CHOOSE, and MSGBOX

  From: Jarno Peschier

  Some examples of INFORM, CHOOSE and MSGBOX on the HP48 GX. Just

  download the entire directory to your calculator and try the programs,

  change them, modify them and do everything else with them you can

  think of.

     SIMPLE:

        This program will demonstrate a simple INFORM input screen with

        3 fields (one without type restrictions, one for real or complex

        numbers and one for strings) with some additional layout. MSGBOX

        and CHOOSE (with the third parameter equal 0) are used to show

        what the results of the INFORM command are. The list the INFORM

        command returns is left on stack so you can see what it looks

        like.

     ANGLE:

        This program will demonstrate the use of CHOOSE. It lets you

        choose between the three possible angle modes (DEG, RAD, GRAD)

        and when you choose one of them, the corresponding mode is set

        by evaluating a tiny program containing the right command.

     ISOLATE:

        This program will demonstrate the use of INFORM in ways that it

        is used in the calculator itself. It is a very simple shell

        around the ISOL command (isolation of a variable from an

        algebraic). It remembers it's settings in a variable called IPAR

        and the next time the program is run this will be the default

        values of the INFORM command, so you can isolate for a different

        variable using the same algebraic you used before, without

        retyping it. MSGBOX is used for error messages.

     TYPELIST:

        This program will again demonstrate the use of CHOOSE. It

        extracts the names of all the internal types of the HP48 GX from

        ROM and shows them in a CHOOSE-box (alphabetically sorted by

        name). If you choose one of them, its TYPE number is shown in a

        MSGBOX.

     MATHQUIZ:

        This final program will demonstrate the use of INFORM with

        variable field descriptions and default/reset values. It's will

        show you 8 fields that are simple math questions for you to

        solve (addition and subtraction).  You can enter all the results

        and then you will see if your answers were correct (in a

        MSGBOX). You must fill all the fields. Hint: you can cheat by

        resetting a field (or all fields).


%%HP: T(3)A(D)F(.);

   DIR

     SIMPLE

       \<<

         IF

   "AN EXAMPLE OF INFORM"

   { { } { } { } {

   "OBJECT:"

   "ALL OBJECTS ARE ALLOWED HERE"

   } { } { "NUM:"

   "ENTER A (COMPLEX) NUMBER"

   0 1 } { "NAME:"

   "ENTER YOUR FULL NAME"

   2 } { } { } } { 3 1

   } {

           \<< 440 1

   BEEP

           \>> (0,1)

   "JARNO PESCHIER" }

   { NOVAL 0 "N.N." }

   INFORM

         THEN DUP

   "YOU ENTERED:" SWAP

   0 CHOOSE DROP

   "The list that INFORM produced is still on the

   stack."

         ELSE

   "You cancelled the INFORM."

         END MSGBOX

       \>>

     ANGLE

       \<<

         IF

   "ANGLE MEASURE" { {

   "Degrees" DEG } {

   "Radians" RAD } {

   "Grads" GRAD } } 1

   CHOOSE

         THEN EVAL

         END

       \>>

     ISOLATE

       \<<

         IF

   "A VERY SIMPLE VARIABLE ISOLATOR"

   { { } { "EXPR:"

   "ENTER THE EXPRESSION"

   9 } { "VARIABLE:"

   "ENTER VARIABLE TO ISOLATE"

   6 } } { } { }

           IF 'IPAR'

   VTYPE 5 \=/

           THEN { }

           ELSE 'IPAR'

   RCL

           END INFORM

         THEN DUP 'IPAR' STO

           IF DUP

   NOVAL POS

           THEN DROP

   "You must enter an expression and a variable!"

   MSGBOX

           ELSE OBJ\->

   DROP

             IFERR

   ISOL

             THEN

   DROP2 "Error: "

   ERRM + MSGBOX

             END

           END

         END

       \>>

     TYPELIST

       \<<

         IF

   "ALL HP48 TYPES (IN ROM)"

   0 27

           FOR msg

             IFERR msg

   263 + DOERR

             THEN ERRM

             END msg 2

   \->LIST

           NEXT 28

   \->LIST SORT 1 CHOOSE

         THEN

   "That one has type number "

   SWAP + "." + MSGBOX

         END

       \>>

     MATHQUIZ

       \<<

         IF

   "A SIMPLE MATH QUIZ"

   1 8

           FOR i "'"

   RAND 100 * IP +

             IF RAND

   0.75 <

             THEN "+"

             ELSE "-"

             END +

   RAND 100 * IP + "'"

   + "ENTER RESULT #"

   i + 0 3 \->LIST

           NEXT 8

   \->LIST DUP

           \<< \-> X

             \<< X HEAD

   2 OVER SIZE 1 - SUB

   "=" + X 1 ROT PUT

             \>>

           \>> DOLIST

   SWAP

           \<< \-> X

             \<< X HEAD

   OBJ\-> EVAL

             \>>

           \>> DOLIST 3

   ROLLD { 2 5 } 4

   PICK { } INFORM

         THEN

           IF DUP

   NOVAL POS

           THEN DROP2

   "You didn't fill all the blanks."

           ELSE

             IF SAME

             THEN

   "All answers were correct!"

             ELSE

   "Not all answers were correct."

             END

           END MSGBOX

         ELSE DROP

         END

       \>>

   END


Some useful LIBEVALs

  9.3.  Some useful LIBEVALs

  From: Joe Horn

  Note well: backup memory before using any of the following!  LIBEVAL

                  can clear memory if used incorrectly.

  Warning to the clueless:

  LIBEVAL, NOT SYSEVAL!!!  If you don't know what a "bint" is, don't use

  the ones that mention bints.

  Example usage: "OUT OF RANGE Try Again" #B0091h LIBEVAL.  Try it!

Function	LIBEVAL
Displays message box with grob	#B1000h
CMD  last command window	#B2000h
CHARS application	#B2001h
MODES application input form	#B41C1h
flag browser  (returns t/f to level 1, just drop it)	#B41CFh
MEMORY application  (aka variable browser)	#B41D7h
SOLVE application choose box	#B4000h
solve equation input form	#B4001h
solve difeq input form	#B4017h
solve polynomial input form	#B402Ch
solve linear systems of equations input form	#B4033h
solve TVM input form	#B4038h
PLOT input form	#B4045h
SYMBOLIC application choose box	#B4113h
integrate input form	#B4114h
differentiate input form	#B4122h
Taylor polynomial expansion input form	#B412Bh
Isolate a variable input form	#B412Dh
solve quadratic input form	#B4130h
manipulate expression input form	#B4131h
TIME application choose box	#B4137h
Set alarm input form	#B4138h
Set time and date input form	#B415Bh
Alarm browser   (aka alarm catalog)	#B416Eh
STAT application choose box	#B4175h
single-var stat input form	#B4176h
frequencies input form	#B417Dh
fit data input form	#B417Fh
summary stat input form	#B418Fh
I/O application choose box	#B4192h
Send to HP48 input form	#B4193h
Print input form	#B4197h
Transfer input form	#B41A8h
Get from HP48  (immediate)	#B50FFh
recalls the contents of the reserve variable Mpar	#E4012h
LIBEVAL:	stack diagram / what it does
#B0091h :	$ --> makes a message box with an alert symbol in it
#E0044h :	$ --> displays a title line, top center (follow with 1 FREEZE if you want it to stay there after program ends)
#B2000h :	launches the Last Command choose-box
#B2001h :	launches the CHARS application; returns nothing if user does not press ECHO
#B2002h :	launches the CHARS application; returns "" if user does not press ECHO
#B41CFh :	launches Flag Browser; leaves a True or False on stack, so follow this LIBEVAL with a DROP.
#B50A3h :	--> current time as hour, min, sec separately, plus an XLIB that represents AM/PM/24-hr (just DROP it)
#B50A4h :	hh.mmss --> hh mm ss xlib (the xlib represents AM,PM, or 24-hr mode; just DROP it)
#B50A6h :	--> current date as month, day, year (always that order, and a two-digit year)
#B50A7h :	mm.ddyyyy (or dd.mmyyyy) --> month, day, yr
#B50A9h :	#month #yr --> #days_in_that_month (inputs and output are bints; year is two digits, interpreted as between 1991 & 2090 only)
#B50AAh :	#yr --> %0.00yyyy (input is two-digit bint interpreted as between 1991 and 2090; output is a real number)
#B50ABh :	#mon #day #yr --> #day_of_week (inputs & output are bints; year is two digits interpreted as between 1991 & 2090; Sunday is #7; if you're in DMY mode, then the input order is #day #mon #yr)
#B50B2h :	--> { 1 2 3 ... 59 } (not very fast)
#B50B3h :	--> { 1 2 3 ... 10 } (very fast)
#B50B4h :	--> { 0 1 2 ... 23 } (very fast)
#B50B9h :	--> { " 1 January" " 2 February" ... "12 December" }
#B50D5h :	--> number of alarms currently set (as a bint)
#E3063h :	hxs --> grob (this is an RLL packed-grob uncompressor, used by EQ LIB and MINEHUNT; for example, try this: #E202Bh LIBEVAL 3 GET #E3063h LIBEVAL PICT STO PICTURE)
#E202Bh :	the first of the packed EQ LIB grobs (see above)
#E2069h :	the last of the packed EQ LIB grobs (see above)
#E7039h :	MINEHUNT packed grob (left screen border)
#E703Ah :	MINEHUNT packed grob (right screen border)
#E801Eh :	obj --> obj T/F (tests whether object is in temporary memory or not; returns System-RPL True or False)


Appendix C: Details of Bugs

10. Appendix C: Details of Bugs

10.1 The EquationWriter Bug

10.2 Rotation Rate to Angular Frequency Conversion Bug


The EquationWriter Bug

  10.1.  The EquationWriter Bug

  From: Joe Horn

     Rev E Behaviour

        Clear flag -53 first (the Precedence Flag).

        On a Rev E, put '((1+2)/(3+4))^5' on the stack and press down-

        arrow.  You'll see:

                    5

          / 1+2 \

          | ------ |                         (A)

          \ 3+4 /

     which is as it should be.  But now press orange-shift +; see the

     message "Implicit () off" momentarily; press left-arrow (not

     backspace), then press the EXIT softkey.  The expression gets man-

     gled into this:

              1+2

          -----------                       (B)

                   5

           (3+4)

     which is not equal to expression (A) above!  Bug, yes?  Press ON to

     abort the process.

     Now set flag -53, then repeat the above procedure.  First you see:

                    5

          / 1+2 \

          | ------ |                         (C)

          \ 3+4 /

     which is the same as (A) above; but continuing as before, you see:

                      (5)

          /  1+2  \

          | ------- |                        (D)

          \ (3+4) /

     which is equal to the original.  Thus the bug can be worked around

     by keeping flag -53 set (not a pleasant solution).

     Rev J Behaviour

        Major difference: after pressing down-arrow, Rev J goes directly

        into graphic mode, so you have to press ON and then EXIT to get

        into the equation editor (which Rev E goes directly into).  But

        that's petty cash compared to the following big change.

        The same sequence of operations, first with flag -53 clear, then

        set, exactly as detailed above, yields these four displays in a

        Rev J:

                      5

          / (1+2) \

          | ------- |                       (A')

          \  3+4  /

     (notice the extra parentheses?) and then:

                    5

        / (1+2) \

        | ------- |                         (B')

        \ (3+4) /

     which is equal to (A'); nothing at all like expression (B) above!

     and then:

                      5

          / (1+2) \

          | ------- |                       (C')

          \  3+4  /

     which is the same as (A') above; and then:

                      5

          / (1+2) \

          | ------- |                       (D')

          \ (3+4) /

     which is also equal to (A').  No bug in Rev J.

  SUMMARY: Rev A-E have a bug in the EquationWriter that can mangle

  expressions if flag -53 is clear (the default) and if "Explicit Paren-

  theses" mode is toggled.  This bug has been fixed in Rev J.

  Unfortunately (as you can see above) Rev J always puts parentheses

  around polynomial numerators.  It is therefore impossible to use the

  ->GROB command on a Rev J to create a GROB that looks like expression

  (A) above; the simplest that can be had is expression (A').

  Another minor change, while I'm at it: Rev A-E don't change the menu

  when you press REPL; Rev J automatically flips to the appropriate

  RULES menu.


Rotation Rate to Angular Frequency Conversion Bug

  10.2.  Rotation Rate to Angular Frequency Conversion Bug

  About the Bug:

     From: Wlodek Mier-Jedrzejowicz <wacm@doc.ic.ac.uk>

     There is a rotation rate conversion bug in the HP48 G/GX which I

     have not seen reported here before, so after discussion with the

     folks at Corvallis I am posting this description. Warning: it is

     159 lines long!

     First - an example. Put the unit object 60_rpm in level 2 and

     the unit object 1_r/s in level 1, then execute the command

     CONVERT.  You are asking the HP48 to convert a rotation rate of

     60 revolutions per minute into an angular frequency in radians

     per second. 60 rpm is 1 revolution per second, or 2pi radians

     per second.  No HP48 G/GX will give this answer!  Not everyone

     uses rpm or is even aware of the existence of this unit - it is

     one of the extra units in the UTILS menu of the Equation Library

     - so here is a second example - add 2pi radians per second to

     one Hertz.  Put 6.2832_r/s in level 1, 1_Hz in level 1, and add.

     You are adding an angular frequency of two pi (one cycle) per

     second to a rotation rate of one per second, so the result

     should be a frequency of two Hertz.  On an HP48 S/SX that is the

     answer.  On an HP48 G/GX it is not.

     When units are converted, by CONVERT, or during arithmetic on

     unit objects, the level 2 object is first turned into "base

     units", and then the result is converted into the units of the

     level 1 object.  On the HP48 S/SX, the "base unit" of angles is

     one rotation (or a "unit circle" or a revolution or a cycle).

     So, the angle unit of rpm (a revolution) or of Hz (a cycle if Hz

     is treated as a rotation rate) is already in base units -

     conversions to angles involving rpm and Hz automatically work

     correctly.  On the HP48 G/GX, the "base unit" of angles is the

     current angle mode (DEG, RAD or GRAD) - so any conversion from

     rpm or Hz (or any formula which works in cycles, rotations,

     revolutions, unit circles) to angles should be preceeded by a

     conversion from the unit circle to the current angle.

     Apparently no-one noticed this would be necessary, because it

     all worked automatically on the HP48 S/SX.

     So, when you convert 60_rpm to units of _r/s, an HP48 G/GX

     converts not 60 rotations but 60 "base angle units" per minute

     to radians/second. In RAD mode, you get 1 radian per second. In

     DEG mode you get 1 degree per second, and in GRAD mode you get 1

     grad per second (in each case expressed in radians). That's

     three different answers, none of which is correct! Exactly the

     same happens if you convert 1_Hz to angles per second, and the

     inverse mistake is made if you convert angles per time to cycles

     or rotations divided by time.

     I first learned of this bug from a member of HPCC (the British

     club for users of HP handhelds), Peter Embrey. He describes his

     troubles in articles in the first two 1994 issues of our club

     journal, DATAFILE (in Volume 13 number 1 pages 12 to 14 and

     V13n2p6). He was calculating the energy stored by a flywheel -

     given by the formula (1/2)*I*omega^2 and after a time he decided

     the answers had to be much too big when he CONVERTed from

     kg*m^2*(r/s)^2 to W*h on an HP48 GX.  It turns out that (r/s)

     are the correct units to get the right answer, but the GX was

     converting to degrees per second as it was in DEG mode, so his

     answer was too large by a factor of (360/2pi)^2 - a factor of

     about 3,300. In this case, his HP48 SX was not much better,

     since it converted from radians to unit circles. The way to get

     the correct answer is to use an HP48 G or GX in RAD mode - or to

     divide out the radians from the formula before using CONVERT.

     This is not yet a bug, but needs as much care as does use of

     temperature units on the HP48. But when Peter tried to deal with

     the problem by working in rpm, he came upon the bug described

     above. My thanks to Peter for putting me on the trail!

     Apparently this bug not been reported before - at least my

     friends in HP tell me that it was not on their list of known

     problems until I told them of it. (This means it is not fixed in

     the new revision R.) Why not - does everyone know about it and

     work around it without thinking to tell anyone else? Or does no-

     one use their HP48 to do calculations on rotating bodies - or do

     most people do calculations with rotating bodies in such a way

     that they do not encounter this problem? Could there be hundreds

     of students and engineers out there calculating and designing

     things on their HP48 G/GX and getting wildly inaccurate results?

     Has anyone built a disk drive or a jet engine which rotates far

     too fast and will disintegrate because of this? No, of course

     not, all engineers know that any design calculation absolutely

     must be repeated on two entirely separate calculators or

     computer programs! :-| Maybe some students have lost marks in

     exams because of this though - but please, this is not intended

     to restart the discussion as to whether calculators should be

     allowed in exams!

     I want to underline again that apparently no-one has reported

     this before - which must mean that few people have been affected

     by it. It is therefore not a good reason to throw away your HP48

     G/GX or get on a high horse and demand that HP replace your HP48

     G/GX - but I think it is important that people be warned so they

     can take appropriate avoiding action. The rest of this message

     goes into more detail - if you never worry about rotation

     calculations then you can safely ignore the rest - though you

     might find it interesting, so don't stop yet :-)

     One way to avoid this would be to add a new unit to the HP48 -

     call it what you like - the "cycle" or "rotation" or

     "revolution" or "unit circle". As I wrote above, this is already

     implied in the HP48 S/SX; to see this on an HP48 S/SX, put 360

     degrees in level 1 and execute UBASE - the result is 1, meaning

     that 360 degrees are equivalent to one base unit of angle

     measurement, but that there is no named HP48 unit corresponding

     to this. In contrast, UBASE on an HP48 G/GX considers the base

     unit of angle measurement to be the radian, even though CONVERT

     behaves as though the base unit is the current angle mode. There

     appear to be two different norms for base angle units on the

     HP48 G/GX!

     The whole subject gets very little mention in HP's manuals. In

     the original HP48 SX manual (two volumes, spiral bound), the

     section on "Dimensionless Units of Angle" in chapter 13, on page

     198, warns the reader about the danger of using dimensionless

     units and states how angle units and scalars are treated. In the

     later HP48 S and HP48 SX manual (one volume), the same warning

     is given in "Converting Dimensionless Units of Angle", on page

     13-12. The HP48 G Series User's Manual, in "Converting Angular

     Units" on page 10-7, says that conversion will interpret a

     scalar according to the current angle mode setting. (A scalar is

     a pure number with no units.)

     For a detailed description, look in the HP48 S/SX edition of

     "HP48 Insights Vol II", section 21.4.3. This book is written by

     Dr Bill Wickes, who was the design team leader of the HP48 SX,

     and who wrote the "Insights" books largely to provide the sort

     of explanations and details that get left out of manuals. A good

     explanation of angle units is exactly the sort of thing one can

     find there! He explains the pitfalls and unavoidable

     contradictions of working with angles in the HP48 units system

     and points out that the HP48 S/SX make the somewhat arbitrary

     choice of using 2pi as the base unit of angles, thereby making

     conversions between angles per time and Hertz work correctly.

     Maybe no-one on the HP48 G/GX team read this while they were

     making changes from the HP48 S/SX! Why did they change the base

     unit at all?  Most likely they were trying to deal with another

     contradiction: the units system lets you add pure numbers to

     angles, since both are dimensionless. If you add the number 1 in

     level 2 to the unit object 0_r in level 1 on an HP48 S/SX, the

     number 1 is treated as 1 base unit, or 2pi radians, and the

     result is 6.2832_r - but if you take the SIN of the number 1

     instead, it is not treated as 2pi, but as 1 unit of the current

     angle mode. The change made on the HP48 G/GX does resolve this

     contradiction, but at the cost of introducing the bug described

     above.

     As mentioned, a way to resolve the problems involved would be to

     add the angle unit "cycle" explicitly to the HP48 units system.

     Hz would then be treated as cycles per second when used in

     calculations involving rotations - rpm would be treated as

     cycles per minute, and conversions would go from cycles to the

     appropriate angle units. This suggestion was made by Peter

     Embrey in his articles, and the folks at HP accept that this is

     a good solution - but they have not implemented it yet. In the

     meantime, be very, very careful when converting between units of

     rotation rate and units of angular frequency. I would urge

     everyone who does not yet have a copy of Insights II to buy one

     and read the relevant section - maybe that will even entice Bill

     Wickes into publishing his long-awaited HP48 G/GX version of the

     book!

     I have not yet mentioned solid angles. In principle there should

     be no problem - on both the HP48 S/SX and the HP48 G/GX the base

     unit of solid angle is a "unit sphere", or 4pi steradians. On

     the HP48 S/SX you can add the pure number 1 to 0_sr and get

     12.5664_sr (4pi steradians). The HP48 G/GX manuals imply that

     exactly the same should happen, but on my (version L) HP48 GX

     this gives the error message "Inconsistent Units".  This is yet

     another undocumented difference between the Series S and Series

     G but at least it is no bug!

     Apologies for making this description so long, I hope most

     people will agree that a subject like this deserves a careful

     description! For my next trick - some details on the HP48 Random

     Number Generator.

  Addition Insight:

   From: Eric Haas <EHaas@ix.netcom.com>

        Note: The < symbol below is actually the angle character.

     The angular conversion bug is actually in the definition of the

     rpm unit.  If you put 1_rpm on the stack, and type UBASE, you

     get 1.66666666667E-2_1/s.  Notice that there is no angular unit

     in the definition. If the rpm unit is instead defined as 6_</s,

     all conversions to and from rpms will work just fine. As an easy

     work-around, define the unit RPM as 6_</s and use that instead

     of the built-in unit.

     If desired, one could also define the unit HZ as 60_rpm or

     360_</s.  However, as Hz is sometimes used to describe things

     other than rotation rates, such a definition would not be

     appropriate for all circumstances.


Appendix D: Hardware Additions

11. Appendix D: Hardware Additions

11.1 How to Make a Serial Cable

11.2 Additional Information on the HP48 and RS-232

11.3 Using Non-HP RAM Cards


How to Make a Serial Cable

  11.1.  How to Make a Serial Cable

  From: Frank Vorstenbosch <prompt@xs4all.nl>

  How to Make a Serial Cable for your HP48

     The Connector for the HP48

        The connector used in your HP48 is a 4 pin (i.e. male)

        connector, with pins spaced 2 mm (NOT 0.1") apart.  These

        connectors are not readily available in stores so you'll have to

        improvise.  If you happen to have a broken floppy drive or

        harddisk lying around, look inside and see if you can find a

        connector there that will fit the HP48.  Do not use a 0.1"

        connector, as this will damage the pins in your calculator.

        If you can't find a usable connector, then you'll have to make

        one yourself.  For this you need four pins taken from a wire-

        wrap IC socket (available from Radio Shack or some other shop

        catering for DIY electronics).  The smallest IC socket available

        usually has 8 pins; so don't worry if you damage a pin while

        removing it from the hard plastic socket.  The pins of the wire-

        wrap socket are about 1" long, thereby making soldering them

        easier than standard sockets.

        Next, solder a 'fork' from thin rigid metal wires, to hold the

        four IC pins spaced at exactly 2 mm while you glue them together

        with superglue.  Glue a plastic 'handle' to the four IC pins to

        be able to remove the connector from the HP48.  You can also

        indicate the top side of the connector on this handle.

        Note that the hole in the HP48 in which the connector should go

        is not symmetrical; the pins are nearer to the top of the

        calculator than the bottom, and you can use this to make it

        difficult to insert the connector the wrong way up.

          Connector to plug

          in your HP48 (F)                           HP48 connector (M)

     Making the Connections

        You can use either a 9 or a 25 pin female sub-D socket for the

        PC-side of the cable.

             9-pin RS232                                          25-pin RS232

            connector (F)                                        connector (F)

     Use flexible 4-wire cable to connect the four contacts of your HP48

     connector to the PC connector.  Pin 1 of the HP48 should be con-

     nected to the metal shield of the RS232 connector.  Usually it is

     not easy to solder this shield; first scratching the shield bare

     (it has some kind of coating) using a screwdriver or a file will

     help.  If this doesn't work, simply leave pin 1 of the HP48 discon-

     nected.  Note that pins 2 and 3 of the RS232 connector must be

     swapped when you use a 25-pin connector.

     HP to PC cable

HP48	RS232-9	RS232-25
1	shield	shield
2	2	3
3	3	2
4	5	7

     Before connecting the completed cable to your HP48, check for

     short-circuits using an ohmmeter or multimeter set to ohms or

     "diode test".

     HP to HP Cable

        If you want to use 9600 bps communication between two HP48s,

        then make two HP48 connectors and simply connect the two,

        swapping pins two and three.

          HP to HP cable

HP#1	HP#2
1	1
2	3
3	2
4	4

      Warranty, Disclaimer, etc...

        Although the serial interface of the HP48 is protected

        internally, it is possible to damage the calculator when a wrong

        connection is made.  I am not responsible for any errors in this

        file, or for any mistakes you may make.

  From: Deborah Lynn Williams

  I made an HP48 link out of four pieces of speaker wire and serial port

  plug.  The wiring of the plug is available above.  The connection to

  the HP plug is the difficult part.

  I took 4 pieces of stranded speaker wire and cut them so that the wire

  and the insulation were even.  I then took a paper clip and pushed it

  into the this open end, making a space between the wire and the

  insulation.  I then had to trim some of the strands that were sticking

  out.  I then just pushed this onto the pins in the HP48 port.  It

  isn't a very strong connection, but it works fine if you don't jostle

  it.

  The other ends of these speaker wires I connected to the serial plug.

  Just remember to label which wires go to which pin, or make them all

  different lengths.

  From: Jeff Dubin

  The HP48 side of the serial port connector can be made with a CD-ROM

  to sound card audio connector.  Take a 4-pin CD-ROM audio connector (I

  used a Mitsumi cable), cut it up and stick a 9 or 25-pin PC serial

  connector on the other end (see pin wiring above).  You may want to

  add a piece of cardboard to the connector for easy removal.


Additional Information on the HP48 and RS-232

  11.2.  Additional Information on the HP48 and RS-232

  From: John Meyers

  You can't connect the HP48 to anything else until you have first

  plugged in its cable, which finally brings the HP48's serial

  connections out to a DB9 connector.  At that point, the HP48,

  including its attached cable, is clearly configured as DCE (the same

  as a modem), so you need a "crossover" (such as a "null-modem

  adapter") to connect the HP48 to a modem.


Using Non-HP RAM Cards

  11.3.  Using Non-HP RAM Cards

  If you use RAM cards that are NOT designed for the HP48, it is

  possible to severely damage your HP48.  If you want to be safe, you

  should only use RAM cards designed for the HP48.

  Here is an edited discussion from comp.sys.handhelds.

  From steveh@hpcvra.cv.hp.com Fri Mar  1 17:00:00 1991

  From: steveh@hpcvra.cv.hp.com (Steve Harper)

  Date: Thu, 10 May 1990 22:46:09 GMT

  Subject: RE: HP48 SX Memory Card Pricing

  Organization: Hewlett-Packard Co., Corvallis, OR, USA

  There has been a substantial amount of comment regarding the memory

  cards for the HP48 SX and their prices.  My purpose in this response

  is not to attempt to justify any particular price, but rather to

  present the technical reasons why there is a substantial price

  difference between the memory cards and other types of expansion

  memory for PC's, for example, with which users are probably more

  familiar.

  Some users have correctly pointed out that the memory in the cards is

  static RAM rather than dynamic RAM commonly used in PC's.  Dynamic RAM

  uses one transistor and a capacitor for each bit of memory whereas

  static RAM requires either four transistors and two resistors, or six

  transistors.  The net result is that an equivalent amount of static

  RAM is much larger and therefore much more expensive than dynamic RAM.

  The advantage is that static RAM doesn't need to continually be

  running and drawing current (refresh cycles) to retain the contents of

  memory.

  In addition, the static memory used in the cards is not just any

  static memory, but is specially processed and/or selected for very low

  standby current.  This allows the backup battery in the card to keep

  memory alive for a very long time, rather than requiring the user to

  replace it every few months.  The special processing and/or special

  testing to select low current parts adds to the already higher cost of

  the static RAM chips.

  The standard molded plastic DIP package used for most integrated

  circuits, including memory chips, is relatively inexpensive because of

  its simplicity and the huge volumes.  Unfortunately, these packages

  are too large to put into a memory card.  Therefore, the card

  manufacturer mounts the individual silicon memory chips directly on a

  special thin PC board together with the memory support chips.  Because

  multiple chips are being placed in a single hybrid package in a

  special process which has lower volume, yields are lower and this

  again causes the cost to be higher.  Indeed, the yield becomes

  exponentially worse as the number of chips and interconnections

  increases in such a packaging process.

  In addition to the memory chips themselves, two more integrated

  circuits and several discrete components are required for power and

  logic control.  A bipolar technology chip senses the external voltage

  and switches the power to the chips from the internal keep-alive

  battery as needed.  A CMOS gate array chip protects the memory address

  and data lines from glitches/ESD when the card is not plugged in.

  This chip also generates the proper enabling signals when there are

  multiple memory chips in the card, as is presently the case with the

  128 Kbyte RAM card.  These chips must be designed for extremely low

  current, just as the memory chips are.

  In addition to the battery and the battery holder, the other

  mechanical parts are important, too.  The molded plastic frame holds

  the PC board and provides the foundation for the metal overlays and

  the shutter-and-springs assembly which protects the contacts from ESD

  and from contaminants.  The write-protect switch is also an important

  feature.  It is quite expensive for the manufacturer to make the tools

  necessary to fabricate each of these parts as well as the tools to

  assemble and test the complete card.  While the volume of memory cards

  is relatively low this tooling cost represents a significant part of

  the cost of each card.

  Admittedly, there are other alternatives, such as those presently used

  in PC's, to provide a memory expansion capability.  To provide that

  kind of expansion would require the calculator to be much larger than

  it is and possibly more expensive.  This is clearly very undesirable.

  Other features that were felt to be essential were the ability to

  distribute software applications and to share and archive/backup user-

  created programs and data.  Other expansion alternatives  do not

  provide these important benefits.  The I/O capabilities of the

  calculator provide these features only to a limited degree.

  One other item bears repeating here: Memory cards for use in the

  calculator will clearly indicate that they are for use with the HP48

  SX.  Other memory cards exist which are mechanically compatible with

  the HP48 S, but these cards cannot be relied upon to work electrically

  in the calculator.  The HP48 SX cards are designed for a lower supply

  voltage range.  Use of the other cards may cause memory loss, and

  under certain circumstances may even damage your calculator

  electrically.

  From steveh@hpcvra.cv.hp.com Fri Mar  1 17:00:00 1991

  From: steveh@hpcvra.cv.hp.com (Steve Harper)

  Date: Fri, 11 May 1990 16:52:07 GMT

  Subject: Re: Memory Card: Give Us True Facts!

  Organization: Hewlett-Packard Co., Corvallis, OR, USA

  My previous statement that under certain circumstances the calculator

  may even be damaged electrically is not a ploy.  If the calculator's

  internal power supply voltage happens to be near the low end of the

  range, say 4.1 V, and the voltage at which the card's voltage control

  chip shuts it down happens to be near the high end of its range, say

  4.2 V (this can and does occasionally occur for the non-HP48 SX

  cards), then the calculator will start to drive the memory address

  lines and the card will still have these clamped to ground (that's

  what it does to protect itself when there is not sufficient system

  voltage to run).  This unfortunate situation may simply trash your

  memory, or if the calculator tries to drive enough of the lines high

  at the same time, several hundred milliamps may flow...for awhile that

  is, until something gives up...  On the other hand, your calculator

  and a particular non-HP48 SX card may work just fine if those voltages

  happen to be at the other end of their ranges.  These voltages are

  also slightly temperature sensitive.  It may work in the classroom or

  office and not at the beach, or vice versa.  The voltage trip point of

  the HP48 SX cards has been set lower (a different voltage control

  chip) so that this cannot occur, regardless of part and temperature

  variations.

  One other item was brought to my attention yesterday by Preston Brown

  that I should have included in my original posting here.  While most

  of us recognize that comparing RAM cards to a handful of dynamic RAM

  chips to plug into your PC is apples and oranges, it may be more

  interesting to compare the HP48 SX cards with cards for other

  products, like the Atari Portfolio, the Poquet, the NEC Ultralite,

  etc.  I believe you will find that the prices on the HP48 SX cards are

  not at all out of line.

  Steve "I claim all disclaimers..."

  From prestonb@hpcvra.cv.hp.com Fri Mar  1 17:00:00 1991

  From: prestonb@hpcvra.cv.hp.com (Preston Brown)

  Date: Thu, 17 May 1990 17:26:53 GMT

  Subject: Re: Memory Card: Give Us True Facts!

  Organization: Hewlett-Packard Co., Corvallis, OR, USA

  When the RAM cards detect that voltage is to low to operate they clamp

  the address lines to ground.  This clamping is done by turning on the

  output drivers of a custom chip included on the card.  The clamping

  current is specified to be 2mA min at the Vol output level.  Since the

  48 can be trying to drive the line all the way high even more current

  is typical.  10mA per fight is not uncommon with totals of several

  hundred mAs.

  The VDD power supply is regulated at 4.1 - 4.9 with typical parts at

  the low end (4.3).  The power to the cards is switched through a

  transistor, creating up to a 0.1V drop.  Standard Epson cards have a

  significant chance of seeing this voltage as to low and shutting down.

  We have seen cards do this in the lab.  When it occurs the calculator

  locks up with VDD pulled down to about 2.5V and 250mA being drawn from

  the batteries.  This current drain greatly exceeds the ratings for the

  power supply and can damage your calc.  The least that will happen is

  a loss of memory.

  Now, why didn't we regulate VDD higher?  The 48 has two power supplies

  VDD at 4.3 and VH at 8.5.  VH cannot be regulated higher without

  exceeding the spec for our CMOS IC process.  VH is used as the +

  voltage for the I/O.  In order to meet a +3V output level VH must be

  more then 3.6V above VDD.  (VDD is used as I/O ground).  Our power

  supply system increase the battery life and reduces the cost greatly

  for the wired I/O.

  Preston


Appendix E: Where to get HP48 Programs

12. Appendix E: Where to get HP48 Programs

12.1 Best Programs and Where to Get Them List

12.2 Other FTP Sites

12.3 FTP by Electronic Mail

12.4 Bulletin Boards with HP48 Programs

12.5 HP Goodies Disks


Best Programs and Where to Get Them List

  12.1.  Best Programs and Where to Get Them List

  This list is designed to help HP48 users locate useful, well written

  programs for their HP48, selected by HP48 users who send in

  recommendations for their favourite programs.

  Compatibility is noted by either SX (SX only), GX (GX only), SX/GX (SX

  and GX), or SX?/GX (Works on GX, not sure about SX).

  Most of the sites below require InterNET access.  However CompuServe

  has a modest HP48 archive in the HP handhelds forum.  Type "go HPHAND"

  to access the forum.  HP48 specific files can be found in DL 3.

  America Online also has an HP area you can access using "Keyword PDA".

  Note that for most FTP sites, any programs in uploads directories are

  subject to movement into their appropriate directories (i.e. games or

  utilities), or removal by the archive maintainer.  There is also the

  possibility that the program might have a slightly different name than

  the one given below, especially if newer versions are available.  If

  information has changed that you know of, let me know so I can update

  the list.

  One site in particular, ftp.cis.com, is intended for G/GX programs

  only.  However the programs in the uploads directory of ftp.cis.com

  are not necessarily GX compatible.  As such, please do not upload non-

  GX compatible programs to ftp.cis.com.  Thanks!

  I have also released my personal HP48 archive, which should be current

  as of July 1996.  It should contain all of the following programs, as

  well as lots of others.  More information can be obtained at my home

  page, <http://www.engr.uvic.ca/~aschoorl/> or at

  <ftp://ftp.cis.com/pub/hp48g/uploads/as-info.doc>

  1.  Applications

  2.  Documents

  3.  Games

  4.  Graphics

  5.  Math

  6.  Programming

  7.  Utilities

  8.  Sound


Applications

    12.1.1. Applications

    •  StringWriter (SX/GX): This is a replacement editor by Jean-Yves

        Avenard.  It offers such features as cut, copy, paste as well as

        a choice of fonts.  Available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/strwrt44.zip>

    •  EXAL (SX/GX): Great spreadsheet program by Al Arduengo.

         Available at <ftp://ftp.cis.com/pub/hp48g/uploads/exalv46.zip>

    •  GxTools (GX): GxTools is in effect a "Toolbar" for your G/GX

        consisting of many useful utilities.  Put together by Jack Levy

        and available at

        <http://www-personal.engin.umich.edu/~levyj/hp48.html>

    •  Organizer (SX/GX): Organizer is a library designed to act as a

        Personal Information Manager, or PIM.  The goal is to create a

        high-speed, easy to use, compact, yet fully functional PIM for

        the HP48.  Organizer includes a calendar, appointment scheduler,

        annual events, TODOs, and a phone manager.  Also by Jack Levy

        and at <http://www-personal.engin.umich.edu/~levyj/hp48.html>

    •  Remote-BG (SX/GX): Use your HP48 as a remote control!  This is

        the best of the remote control programs and has the ability to

        learn new codes.  By Bjorn Gahm, available at

        <ftp://nada.kth.se/home/d89-bga/hp/files/posted/rem34bg.zip>

    •  Scribe (SX/GX):  Scribe is a library which will function as a

        Database or Rolodex.  It is designed to hold a large amount of

        information in such a manner that it is easy to retrieve, quick

        to find, and transparent in usage.  Another great program from

        Jack Levy at

        <http://www-personal.engin.umich.edu/~levyj/hp48.html>


Documents

    12.1.2. Documents

    •  FAQ (SX/GX): Contains valuable answers to Frequency Asked

        Questions.  Read it!  The latest version is available at

        <http://www.engr.uvic.ca/~aschoorl/faq/>.

    •  GX Programming Tips (SX/GX): This document by Doug Cannon

        briefly describes how to write code that runs on both SX and GX.

        Available at

        <ftp://ftp.cis.com/pub/hp48g/programming/gxtips.zip>

    •  Library Info (SX/GX): Information on the structure and use of

        libraries.  By Charlie Patton.  Available on Goodies Disk 8.

    •  ML Input (SX/GX): How to get keyboard input from ML.  By Joe

        Ervin.  Available on Goodies Disk 7.

    •  RPLMAN.DOC (SX/GX): This document was written by HP and released

        without support to HP48 users.  It describes how to program in

        System RPL.  Available on Goodies Disk 4.

    •  Saturn (SX/GX): Saturn Processor Reference guide by Matthew

        Mastracci.  The URL is

        <http://www.ucalgary.ca/~mmastrac/saturn.doc>

    •  SASM.DOC (SX/GX): Also from HP, this is the unsupported guide to

        machine language programming for the Saturn processor.

        Available on Goodies Disk 4.


Games

    12.1.3. Games

    •  Arkanoid (SX/GX): Breakout clone with editor - by "HP Mad".  SX

        version available on Goodies Disk 8.  There is also a GX version

        floating around, try

        <ftp://ftp.cis.com/pub/hp48g/uploads/as-games.zip>

    •  Boulder DasHP (SX): Classic game of Boulder Dash by David Presle

        "ORUS".  Get the diamonds without getting smashed by falling

        rocks or running into enemies.  Available on Goodies Disk 8.

    •  Columns (SX/GX): Tetris-like game by Spartacus.  Available at

        <ftp://ftp.cis.com/pub/hp48g/games/columns.zip>

    •  Columns II (GX): Columns with grey scale for GX only, again by

        Spartacus.  Available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/columns2.zip>

    •  Diamonds (SX/GX): Great game by Doug Cannon!  Control bouncing

        ball to get the diamonds.  Available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/diam20.zip>

    •  ICE Cube (SX/GX): Great action arcade game in four levels of

        grey scale by Lilian Pigallio.  Available at ftp.cis.com.

    •  Jytris (SX/GX): One of the best tetris games including music,

        cartoons, bombs, and grey scale intro.  Written by Laurent

        Jouanneau.  Separate libraries are available for all HP48s

        (including minimized libraries for S and G).  All of which are

        available at ftp.cis.com.  In particular, the GX version is at

        <ftp://ftp.cis.com/pub/hp48g/uploads/jytrisgx.lib>

    •  Hapaman (GX): PacMan clone by Davor Jadrijevic.  Available at

        <ftp://ftp.cis.com/pub/hp48g/games/hapaman.zip>

    •  La Mine aux Diamants (SX/GX): Another Boulder Dash clone.  By

        Lilian Pigallio.  Available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/diamants.uue>

    •  Lemmings (SX/GX): Save the lemmings from killing themselves!  By

        C. de Dinechin.  GX version is available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/lemprog.gx> and SX version

        is at

        <ftp://ftp.stud.fh-heilbronn.de/pub/hp48/game/arcade/lemmings/lemmingsx.zip>

    •  LodRunner (GX): LodeRunner clone for the HP!  By HPOWER, with

        improvements from Mika Heiskanen.  Available at ftp.cis.com.

    •  Phoenix (SX/GX): Phoenix clone by Davor Jadrijevic.  GX version

        is available at <ftp://ftp.cis.com/pub/hp48g/games/phoenixg.zip>

        and SX version is at

        <ftp://ftp.stud.fh-heilbronn.de/pub/hp48/game/misc/phoenixs.zip>

    •  Quick Reversi (SX): Fastest Reversi by Leon Pavlov.  Quite

        smart!  Available on Goodies Disk 8.

    •  Tetris (SX/GX): Tetris clone - small, fast, great!  By Detlef

        Mueller.  Available at wuarchive.wustl.edu.

    •  SCHIP (SX/GX): Video game interpreter for SCHIP designed games.

        By Erik Bryntse.  SX version available on Goodies Disk 3.  GX

        version available at

        <ftp://ftp.cis.com/pub/hp48g/games/schipgx.zip>

    •  Vaders (SX/GX): Space Invaders by Joe Ervin.  Available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/vaders21.zip>

    •  Willy (SX/GX): Side scroller game by Mario Mikocevic.  Available

        at <ftp://ftp.cis.com/pub/hp48g/games/willy.zip>


Graphics

    12.1.4. Graphics

    •  4 Colors (SX/GX): Utilities for making four shade greyscale

        graphics.  By Lilian Pigallio and available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/4colors.zip>

    •  Claudia (SX/GX): Greyscale demo of Claudia Schiffer, the

        supermodel.  By Mohamed Fatri.  Available at

        <ftp://ftp.cis.com/pub/hp48g/graphics/claudia.zip>


Math

    12.1.5. Math

    •  ALG48 (SX/GX): Very fast algebraic manipulation utilities by

        Mika Heiskanen and Claude-Nicolas Fiechter.  Available at

        <http://www.hut.fi/~mheiskan/>

    •  ALGB (SX/GX): Tons of powerful math utilities!  By Bernard

        Parisse.  Latest beta version is always at

        <ftp://puccini.ujf-grenoble.fr/pub/hp48/algbtest.zip> and the

        currently released version is at

        <ftp://puccini.ujf-grenoble.fr/pub/hp48/algb.zip>

    •  CNTR (SX/GX): Discrete and continuous control systems design;

        Inverse Z and Laplace Transforms.  By Cesar Crusius.  Available

        at <ftp://ftp.cis.com/pub/hp48g/uploads/cntr300.zip>

    •  EQSTK (SX/GX): 7-line replacement stack intended for

        mathematics.  View objects on the stack in their native form

        (see also Java, a more generalized stack program).  By Mika

        Heiskanen.  Available at <http://www.hut.fi/~mheiskan/>

    •  Math (SX/GX): Symbolic/numerical matrices and polynomials by

        Cesar Crusius.  Available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/math210.zip>

    •  Matrix (SX/GX): Very fast matrix writer replacement by Arnold

        Moy.  Handles real and complex matrices, and uses the UFL small

        font for its display.  Available at

        <http://www.geog.ubc.ca/~amoy/>

    •  MTools (SX/GX): MathTools by Jack Levy.  Faster and friendly

        replacements for the HP's math functions.  Available

        <http://www-personal.engin.umich.edu/~levyj/hp48.html>

    •  QPI (SX/GX): Replaces ->Q, shows quotients, and functions of pi,

        radicals, LN and EXP.  Very useful!  THe latest version can be

        found at <http://www.hut.fi/~mheiskan/>.

    •  SolveSys (GX): Solves systems of equations.  By Sune Bredahl.

        Available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/solvesys3a.zip>


Programming

    12.1.6. Programming

    •  Jazz (SX/GX): This is best System RPL and Machine Language

        development library that runs right on your HP48!  Written by

        Mika Heiskanen.  The Jazz library provides commands for

        assembling, disassembling and debugging both System RPL and

        machine language.  Latest full version is available at

        <http://www.hut.fi/~mheiskan/> and corresponding light version

        at <http://www.engr.uvic.ca/~aschoorl/>

    •  HP's Tools (DOS): Development tools for System RPL and libraries

        on the PC.  On Goodies Disk 4.

    •  GNU-Tools (Unix, DOS): A set of replacements for HP's

        development tools by Mario Mikocevic (Mozgy) which that not only

        runs on DOS, but also typical Unix systems such as Linux and

        Solaris.  It is distributed in both source and binary form.

        Many of the larger HP48 programs like Jazz, Java, and the UFL

        were developed with GNU-Tools.

        It is available at:

    •  <ftp://gnjilux.cc.fer.hr/pub/hp48/gtools/>

    •  <http://www.zems.fer.hr/~mozgy/jwz/hp48.html>

    •  SSS (SX/GX): The SysRPL Shell by Stefan Wolfrum provides an

        interface that helps you program in System RPL.  Available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/sss22.zip>


Utilities

    12.1.7. Utilities

    •  BKUP (SX/GX): BKUP is written entirely in System RPL and is

        intended to make a backup of any port(s) the user specifies.  By

        Bob Apodaca, available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/bkup46.zip>

    •  FF (GX): This File Finder is designed for users with large

        directory structures.  It accepts a string and will search your

        directories recursively for matches.  By Jorge Costa and

        available at <http://alfa.ist.utl.pt/~l38861/>

    •  FIXIT (SX/GX): This program by Mika Heiskanen and Joe Horn

        repairs "HPHP48-" bad downloads.  Available in ASC format in the

        FAQ as well as on Goodies Disk 8.

    •  FXRECV (GX): Fixes bug in X-Modem for G/GX.  Not necessary for

        Rom R.  By Cary McCallister.  Available on Goodies Disk 9.

    •  HP82240B Emulator: Allows you to emulate the HP82240B IR

        Printer.  Written by Jarno Peschier and at

        <http://www.students.cs.ruu.nl/people/jpeschie/>

    •  Java (SX/GX): The totally improved 5-line stack environment!

        Includes lowercase menus, improved status area, on-stack

        algebraics, improved interactive stack, configurable font,

        scroller, fast ML routines and more.  By Richard Steventon and

        Andre Schoorl (hey that's me!).  The latest released version

        (2.9a) is available at <http://www.engr.uvic.ca/~aschoorl/>

    •  PCT (SX/GX): Both SX and GX versions are available of this file

        and library maintenance program.  Available at the standard

        sites.  Be sure to use the correct version for your machine!  In

        particular the TREE.PCT file is an S/SX program that is a common

        cause of crashes on G/GX machines.

    •  UFL (SX/GX): The Universal Font Library provides a centralized

        location for common fonts between programs.  Also comes with a

        Font Maintenance Library (FMnt).  Maintained by Andre Schoorl

        and available at <http://www.engr.uvic.ca/~aschoorl/ufl/>

    •  USEND/URECV (SX/GX): Significantly faster IR file transfers!

        Approximately 4 to 6 times faster than SEND.  By Dan Kirkland.

        Available at <ftp://ftp.cis.com/pub/hp48g/utilities/usnd3.dk>

     •  STOFIX (GX): Fixes STO bug on Roms L and M.  By Detlef Mueller.

        Available at <ftp://ftp.cis.com/pub/hp48g/utilities/stofix.zip>


Sound

    12.1.8. Sound

    •  Tricorder (SX/GX): This program will make your HP48 beep when it

        is held close to an object using the IR port.  Great for amusing

        friends!  Written by Steven Ourada, and available at

        <ftp://ftp.cis.com/pub/hp48g/uploads/tricorde.zip>


Other FTP Sites

  12.2.  Other FTP Sites

  •  <ftp://ftp.cis.com/pub/hp48g/>

  •  <ftp://hpcvbbs.external.hp.com/dist/>

  •  <ftp://oprfhs.org/pub/hp48/>

  •  <ftp://ftp.stud.fh-heilbronn.de/>

  •  <ftp://ftp.cyberbox.north.de/pub/pockcomp/hp48/>

  •  <ftp://ftp.cyberbox.north.de/pub/pockcomp/fileecho/hp48/>

  •  <ftp://hplyot.obspm.fr/hp48/>

  •  <ftp://wuarchive.wustl.edu/systems/hp/hp48/>

  •  <ftp://ftp.ee.ualberta.ca/pub/HP48/>

  •  <ftp://oak.oakland.edu/pub/ham/hp48/>

  •  <ftp://ftp.polymer.uakron.edu/pub/hp48g/>

  •  <ftp://nic.funet.fi/pub/misc/hp48g/>

  •  <ftp://nada.kth.se/home/d89-bga/hp/>

  •  <ftp://ftp.fht-mannheim.de/pub/hp48/>


FTP by Electronic Mail

  12.3.  FTP by Electronic Mail

  For those of you who don't have FTP access, you can FTP programs by

  mail.  To do this, you send commands via email message to the ftpmail

  server, and it then sends back the programs, usually in a uuencoded

  format by email.

  For access to any ftp site, I recommend the sunsite ftpmail server.

  To get more information, send a mail message to

  <ftpmail@sunsite.unc.edu> with the contents of:

       help

       quit

  There are other FTP by mail servers like the sunsite server, but they

  are more heavily used, and take longer.


Bulletin Boards with HP48 Programs

  12.4.  Bulletin Boards with HP48 Programs

     Official Hewlett Packard BBS (48)

     •  Phone: (208) 344-1691 ; Corvallis, Oregon.

     •  Second Node: (541) 715-3277 ; Speed: 9600 baud

     Foundations in Science (48/100)

     •  Phone: (206) 562-7083 644-2723 ; Speed: 14.4

     •  Contact: <civan@eskimo.com>

     UAH ACCESS BBS (28/48/95/100)

        Phone: (205) 895-6152 ; U. Alabama Huntsville.

     The Ninth Bit BBS (48)

     •  Phone: (405) 372-7204 ; Speed: 14.4

     •  Contact: <scott.wilkins@ninth.ucc.okstate.edu>

     Raiders of Lost Arg (48/95)

     •  Phone: (416) 968-6633 ; Speed: 38400 N81

     •  Contact: <john.ricciuti@can.rem.com>

     NES BBX (48)

        Phone: (503) 640-4263 ; Goodies Disks in File Area 22

     (hp)al BBS (48/95/100)

     •  Phone: (612) 642-5906 ; Features: Usenet, E-Mail

     •  Contact: <rab@lydia.mn.org>

     Electronic Design News BBS (48)

        Phone: (617) 558-4582 ; Features: Open to All

     Nybble's Byte (28/48/95/100/etc)

     •  Phone: (708) 304-0666 ; Speed: 28.8

     •  Features: 24 hr. Usenet/Internet

     Terrapin Station (48)

        Phone: (708) 657-9543

     48 Files BBS (48)

     •  Phone: (801) 371-8760 ; Speed: 14.4

     •  Features: Over 3000 files

     The ONE BBS (48)

        Phone: +33-149-887-691 ; France.

     Cyberbox (48)

     •  This German BBS has a filebase that contains about 1000 Files,

         30MB.  All are zipped, with descriptions.

     •  Contact: Patrick_Werner@cyberbox.north.de

     •  Phone:

     •  Line 01      : +49-441-3990031  USR 2400-33600

     •  Line 02-04 : +49-441-3990032  USR 2400-14400

     •  Line 05-08 : +49-441-3990033  USR 2400-33600

     •  There is also full access to the filebase at

        <http://www.cyberbox.north.de/> with a description to all the

        files (you can find the descriptions in POCFILES.ZIP in

        pub/pockcomp/hp48).


HP Goodies Disks

  12.5.  HP Goodies Disks

  The HP Goodies Disks are a set of disks that are chock full of great

  HP48 files.  They are collected by Joe Horn, and sold at cost through

  EduCalc.  They contain all shareware/freeware files.  Currently there

  are 10 disks.  They can be obtained via anonymous ftp from the places

  listed below, or they can be purchased from EduCalc. In the listings

  above, they are referred to by "GD #".  All the goodies disks have a

  file "fileinfo.src" which contains an index of all the files.  I would

  recommend everybody looking through all these disks, as there is lots

  of great stuff on them!

  •  EduCalc: 1-800-677-7001

  •  <ftp://wuarchive.wustl.edu/systems/hp/hp48/EduCalc/>

  •  <ftp://ftp.ee.ualberta.ca/pub/HP48/>

  •  UAH BBS: (205) 895-6152

  •  CompuServe: go HPHAND ; DL 3


Contributors

  13.  Contributors

  The maintainer thanks the following international contributors

  (covering a total of 16 countries) for their invaluable help in

  compiling this FAQ:

     U.S. and Canada:

        Dave Arnett, Allen Arnold, Rich Brown, Doug Cannon, Dallan

        Christensen, James Cook, Andrew Dooley, Chuck Dinsmore, Jeff

        Dubin, Egan Ford, John Goerzen, Paul Hart, Joe Horn, Jack Levy,

        Keith Maddock, Scott Marlowe, Thomas De Matteis, John Meyers,

        David Moisan, Derrik Pates, David Peterson, Othniel Rawlins,

        David Rice, Ray Richardson, Maynard Riley, Jeremy Smith, Chris

        Spell, Lee Studley, Deborah Lynn Williams, Mark Wilson, Patrick

        Yagle.

        Jean-Francois Larin, Arnold Moy, Jeff Sketchley, Matt Willis,

        Ryan Youck.

     Europe:

        Rachid Benzaoui (France), Jorge Costa (Portugal), Yves Gadioux

        (France), Bjorn Gahm (Sweden), Maarten van den Hoek

        (Netherlands), Pieter-Bas IJdens (Netherlands), Jens Kerle

        (Germany), Wlodek A C Mier-Jedrzejowicz (U.K.), Mario Mikocevic

        "Mozgy" (Croatia), Makoto Miyamoto (Germany), Jarno Peschier

        (Netherlands), Lilian Pigallio (France), Rob Simpson (U.K.),

        Klaus Wolferts (Germany), Stefan Wolfrum (Germany), Stevens

        Wouter (Belguim), Matjaz Vencelj (Slovenia).

     Elsewhere:

        Guido Carvajal (Chile), Cesar Crusius (Brazil), Kevin Cheng

        (Australia), Antonio Pacheco (Venezuela), Richard Steventon

        (South Africa).