A few questions concerning HP calculators



#2

Hello,


I'm kind of HP addict for calculators and I have a few questions in mind:


HP 50G:

- Does this calculator include all the development tools for assembly programing (i.e. MASD, StringWriter...)?

- Are programs already written (and downloadable) to take advantage of the ARM processor?

- Is there already a successor programmed yet (HP 51 G?)

- What is the future to HP's calculators (compared to other ClassPad / Nspire)? In other way, will kind of Xpander calculator show up sometimes in the future?


HP 71B:

- Is it possible to program this calculator in assembly language without the (expensive) ASM/FORTH module? If not, is they another way to finding this module cheap enough? Can theses modules be copied (RAM, EPROM) in some way?

- How to connect this calculator easily to a PC (using HP-IL interface)?

- Is there a trick to expand memory without installing the (again expensive) Corvallis memory module?

- What is the biggest memory Corvallis produced for this calculator, and are they still available?


HP 48SX:

My screen is defective: 1 entire column is missing pixels. How can I (if possible) change the screen to a new one? Is it worth the effort, or should I jump directly for a HP 50G?


Thanks for reading!


Chris.


#3

Hi, Chris:

Chris posted:

    "HP 71B: - Is it possible to program this calculator in assembly language without the (expensive) ASM/FORTH module? If not, is they another way to finding this module
    cheap enough?"

      The easiest, cheapest, and fastest method by far would be to do all your HP-71B development using the freeware HP-71B emulator Emu71 running on a Windows PC. The FORTH/Assembler ROM image is freely available as well (as are many other important ROMs and LEX files, such as the Math ROM) and it typically runs at least 350x faster, which means entering and assembling long assembler source code file is both feasible and convenient. Emu71 also emulates large amounts of RAM as well, HP-IL disk drives, and an 80-column HP-IL display for easy editing.

      Once assembled, you would have to transfer the resulting BIN or LEX file to your physical HP-71B, if desired. This can be done but I'll let the explanation to other people more knowledgeable than me. In any case, you can contact Emu71's author for the details.

    "What is the biggest memory Corvallis produced for this calculator, and are they still available?"

      I do own a 128 Kb Corvallis RAM module, which plugs in the card reader port. I got it from eBay for $90 at the time. It looks very nice when plugged in, what with the deep dark reed and gold lettering.

Best regards from V.


#4

Hi Valentin,

Quote:
    The easiest, cheapest, and fastest method by far would be to do all your HP-71B development using the freeware HP-71B emulator Emu71 running on a Windows PC. The FORTH/Assembler ROM image is freely available as well (as are many other important ROMs and LEX files, such as the Math ROM) and it typically runs at least 350x faster, which means entering and assembling long assembler source code file is both feasible and convenient. Emu71 also emulates large amounts of RAM as well, HP-IL disk drives, and an 80-column HP-IL display for easy editing.

    Once assembled, you would have to transfer the resulting BIN or LEX file to your physical HP-71B, if desired. This can be done but I'll let the explanation to other people more knowledgeable than me. In any case, you can contact Emu71's author for the details.


I've downloaded Jean-François' software, though I havn't used it yet. My point was to use my calculator to program (easier to carry, and BTW, I love the contact of theis calculator when keys are pressed!) rather than my computer ;-).

#5

Hi again, Chris:

Chris posted:

    "I've downloaded Jean-François' software, though I havn't used it yet. My point was to use my calculator to program"

      Yes, I understand your feelings, so to say, but I own and have extensively used the real, physical FORTH/Assembler ROM plugged in a physical HP-71B and entering, debugging, and assembling source code is a real pain, incredibly slow, error prone, tiring, time-consuming, and ultimately frustrating.

      Even a short assembler source code file requires a lot of time to compile, and if there's some error, you'll have to debug and repeat the compilation any number of times. Memory consumption is also very high, and it all combines to the point where assembling moderate size source code files is either out of the question of you must be willing to spend many, many hours, and have many, many K's of free RAM to allocate to the task.

      None of those problems apply when running a 350x-faster emulation loading its large, fully-commented source code from emulated disk, with 128 Kb of emulated RAM in a 80-colum x 50-line full-screen display with a life-size PC keyboard. This takes away all the frustration and lets you concentrate in the assembler code instead. Then you can transfer your brand-new, shiny LEX file to your physical HP, if you want to use it there.

    Just some friendly advice.

Best regards from V.


#6

Quote:
"Even a short assembler source code file requires a lot of time to compile, and if there's some error, you'll have to debug and repeat the compilation any number of times. Memory consumption is also very high, and it all combines to the point where assembling moderate size source code files is either out of the question of you must be willing to spend many, many hours, and have many, many K's of free RAM to allocate to the task."

Hum... I understand what you mean. I won't bother finding this rather expensive module in that case. Thanks Valentin for sharing your experience.

Now I need to find how to download le LEX files from my computer.
#7

Hi, Chris;

Quote:
- What is the future to HP's calculators (compared to other ClassPad / Nspire)? In other way, will kind of Xpander calculator show up sometimes in the future?
I'd guess neither HP would try an answer to that. Users are the ones to determine such future, i.e., will users be using HP calculators in the future? My HP41C helpped me to understand many engineereing situations once I decided to write programs to help solving them. And understanding RPN allowed me to reason in a different way when solving prblems. I think not too many people care too much for these subjects.
Quote:
HP 48SX:
My screen is defective: 1 entire column is missing pixels. How can I (if possible) change the screen to a new one? Is it worth the effort, or should I jump directly for a HP 50G?
First, one must be sure where is the problem. I have an HP42 with two columns and one row missing in the display. I replaced the LCD (a dead HP17BII) and the same lines were off. The problem was in the processor. As many of us have already seen, the HP42 has a single chip with ROM, keyboard and LCD interface included (RAM is external). So, there is no way to repair such thing. I have once replaced an HP48G LCD, and the fact is that it must be comletely disassembled: the LCD itself is glued to a metal frame that can only be removed after breaking many plastic rivets that are accessible only after opening the calculator (plastic lockers and other rivets) and removing the main PCB (fixed in place with six twisted metal tabs). I'd not do taht again unless it is a vintage HP48SX needing a new LCD (my HP48SX has a spot in the LCD; I have one spare HP48G carcass, and I am not willing to open the HP48SX so far...). To be honest, I'd give a new H50G a try.

Not much of a help, I know, but I'd like to think of it as my 2¢.

Success.

Luiz (Brazil)

Edited: 1 Oct 2007, 10:51 a.m.


#8

Hi Luiz,

Quote:
I'd guess neither HP would try an answer to that. Users are the ones to determine such future, i.e., will users be using HP calculators in the future? My HP41C helpped me to understand many engineereing situations once I decided to write programs to help solving them. And understanding RPN allowed me to reason in a different way when solving prblems. I think not too many people care too much for these subjects.
Question is: is there an ear listening somewhere in HP's office? For instance, could the next calculator have the same feeling when pressing a key compared to my 48SX? What about using a 16 or 256 grey level LCD display? ...

Quote:
Not much of a help, I know, but I'd like to think of it as my 2¢.
On the contrary, it helps. I'll continue using my poor old 48SX that way instead of trying doing my Mac Giver's sort of thing (I have no particular skills in micro electronics...).

The HP50G seems a good calculator if I can use some already implemented assembly langage programming tools.

#9

Hi, Chris (some spare time, again);

Quote:
The HP50G seems a good calculator if I can use some already implemented assembly langage programming tools.

About assembly language: I'm a Z-80, 8086-scratcher, meaning that I learnt how to program in assembly language with those guys... an actual bit-shrinker.

Assembly language demands hardware (internal processor architecture), peripheral and OS knowledge, unless you are programming in a second- or third-layer, i.e., an emulator. I first read about resident emulation with the Transmeta´s Crusoe documentation. In this case, assembly documentation itself may fill the blanks.

I felt a bit disappointed after getting together many documentation about the Saturn assembly and then knowing that the new HP48/49/50 use ARM architecture instead... Learning assembly fundamentals is not that hard, what bothers me is to transpose existing knowledge base to new mnemonics, register set, addressing, flags... I guess new programming tools might provide existing codes to be ported, though.

Let us know if there is any news, O.K.?

Success!

Luiz (Brazil)

Edited: 1 Oct 2007, 5:40 p.m.


#10

Quote:
I felt a bit disappointed after getting together many
documentation about the Saturn assembly and then knowing that the
new HP48/49/50 use ARM architecture instead... Learning assembly
fundamentals is not that hard, what bothers me is to transpose
existing knowledge base to new mnemonics, register set,
addressing, flags... I guess new programming tools might provide
existing codes to be ported, though.

Almost everything that you learned about hardware Saturn assembly
still applies to the ARM-based models. What you may well want to
learn are new syntax rules and new features for the new
programming tools. True, the new Saturnator is an emulated
processor running in the ARM system, but it includes everything
that's in the legacy hardware Saturn, as well as a good many new
assembly language instructions.

The new instructions may make things easier, but you don't have to
use them; it's your choice. For example, note that the ROMs for
the emulators included with Debug4x don't use any of the new
opcodes or access the ARM system, yet all of the legacy
hardware Saturn and 49 series RPL code can be used with the
emulators.

Regards,
James

#11

Hi Luiz,

Quote:
About assembly language: I'm a Z-80, 8086-scratcher, meaning that I learnt how to program in assembly language with those guys... an actual bit-shrinker.
I learnt assembly language on both Z-80 (I also own a Sharp PC-1600) and SC61860 (sharp's other pocket computers), so I'm not afraid to program a 4 bit processor!
Quote:
I felt a bit disappointed after getting together many documentation about the Saturn assembly and then knowing that the new HP48/49/50 use ARM architecture instead... Learning assembly fundamentals is not that hard, what bothers me is to transpose existing knowledge base to new mnemonics, register set, addressing, flags... I guess new programming tools might provide existing codes to be ported, though.
As long as programming the Saturn is still possible, I don't bother.

The only thing I find interresting in the HP49 series is the possibility to program the ARM directly on the calculator (if such a tool is available somedays).


Chris.
#12

Quote:
Question is: is there an ear listening somewhere in HP's office?

Based on the release of the 50g and 35s, I expect that someone at
HP has been listening. I can't be absolutely certain that any
current HP employees monitor this Museum Forum, but
Cyrille de Brebisson
occasionally posts to comp.sys.hp48.

Quote:
For instance, could the next calculator have the same
feeling when pressing a key compared to my 48SX?

The 50g's keyboard doesn't seem as nice as the 48 series, but it's
certainly an improvement over the 49G and early 49g+ units; maybe
someday....

I suspect that my 48SX's keyboard may be somewhat "softer" than
when it was new.

Quote:
What about using a 16 or 256 grey level LCD display? ...

I don't have any experience with it, but do some searches for
"greyscale" (or perhaps "grayscale") and "OpenFire" at
comp.sys.hp48 and hpcalc.org.

Quote:
The HP50G seems a good calculator if I can use some already
implemented assembly langage programming tools.

You can, if you want to. However, many entry points have changed,
so for any RPL code, the new Suprom49 files should be used.

All of the legacy hardware Saturn opcodes from the 48 series still
work in the ARM-based models. Of course, if you want to use new
tools, such as the built-in MASD, some adjustments to the source
code syntax will be needed.

Regards,
James

#13

- Does this calculator include all the development tools for assembly programing (i.e. MASD, StringWriter...)?

http://groups.google.com/group/comp.sys.hp48/browse_thread/thread/e5c9e2a946f350c8/

- Are programs already written (and downloadable) to take advantage of the ARM processor?

Yes. Not as many as in sysRPL and such. COming from and SX though, anything will be so much faster you won't care if it is saturn or ARM at all.

TW


#14

Hi Tim,

Quote:
http://groups.google.com/group/comp.sys.hp48/browse_thread/thread/e5c9e2a946f350c8/
Thanks for this interesting URL. I also gained some information on this post: http://groups.google.com/group/comp.sys.hp48/browse_thread/thread/84c0f5aa19f39cf6/4d48618956d5aa4a#4d48618956d5aa4a

Quote:
COming from and SX though, anything will be so much faster you won't care if it is saturn or ARM at all.
Whenever I put a hand on this calculator, I'll post my comments in this folder!
#15

Quote:
Does this calculator include all the development tools for assembly programing (i.e. MASD, StringWriter...)?

The same tools for the 48 should work for the 50g Saturn emulation.

Quote:
Are programs already written (and downloadable) to take advantage of the ARM processor?

Yes. There are a few. Recently I posted a PI program written in C and cross compiled for the ARM processor. It can compute 15000 digits of PI in < 7 minutes and save the output to the SD card.

Quote:
How to connect this calculator easily to a PC (using HP-IL interface)?

You need an HP-IL ISA adapter and a PC with an ISA slot and the registered version of EMU71. One you have this setup you can transfer from 71B <-> EMU71 as if EMU71 was a 71B.

Optionally you can get an HP-IL/RS-232 device.

Lastly you can always key in BASIC and with a BASIC program object code.

Quote:
or should I jump directly for a HP 50G?

Yes.

#16

Quote:
Yes. There are a few. Recently I posted a PI program written in C and cross compiled for the ARM processor. It can compute 15000 digits of PI in < 7 minutes and save the output to the SD card.
Is there a repository website dedicated to these programs?

Quote:
You need an HP-IL ISA adapter and a PC with an ISA slot and the registered version of EMU71. One you have this setup you can transfer from 71B <-> EMU71 as if EMU71 was a 71B.
Not very easy for me (and probably expensive too).

I'm surprised that nobody worked on a HP-IL <-> USB adapter, considering the size of HP calculator's community.

The only drawback with keying programs is loss of data, without possibility of saving months of work :-(.

#17

Quote:
Is there a repository website dedicated to these programs?

hpcalc.org has a few, grouped by function, not by language. It is a small community, the best place for examples are the examples included with HPGCC. Use the HPGCC mailing list and comp.sys.hp48 for support.
Quote:
Not very easy for me (and probably expensive too).

  1. HP-IL ISA Adapter: ~$50 (if you can find one).
  2. Old ISA PC: ~$20 (thrift store).
  3. Software ~20 Euros.
  4. 71B HP-IL Adapter: ~$50-$100
  5. Two cables: ~$50
The alternative is RS-232/HP-IL.
  1. HP-IL/RS-232 Gateway: ~$125 (one/month on eBay).
  2. 71B HP-IL Adapter: ~$50-$100
  3. Two cables: ~$50
IMHO, if you value your time and data the first solution is inexpensive. The 2nd is more time consuming.

If you are only looking for backup:

  1. 9114B floppy drive: ~$200-$300 (one known working/month on eBay).
  2. 71B HP-IL Adapter: ~$50-$100
  3. Two cables: ~$50
Quote:
I'm surprised that nobody worked on a HP-IL <-> USB adapter, considering the size of HP calculator's community.

I'd be surprised if someone created an HP-IL <-> USB adapter, considering the size of legacy HP calculator's community. :-)

Edited: 3 Oct 2007, 12:31 p.m.

#18

Quote:
HP 50G:


In general, the usenet group comp.sys.hp48 specializes in
discussions of RPL models, and many downloads are available from
http://www.hpcalc.org/.
Quote:
- Does this calculator include all the development tools for
assembly programing (i.e. MASD, StringWriter...)?

The 49 series (49G, 49g+, 48gII, and 50g) have MASD built-in, as
part of the "Development Library" application. However, to use
mnemonic SysRPL command names, an extable library needs to be
installed. Without extable installed, numeric pointers can be
used. The extable library supplied by HP includes the supported
entry points, and the extable2 library included with Emacs also
includes some "unsupported but stable" entry points. You could
also make a "customized" extable library with whichever entry
points you chose.

With the ARM-based models (49g+, 48gII, and 50g), the Saturn
processor is emulated, and includes additional assembly language
instructions; this emulated processor is sometimes referred to as
the "Saturnator" or "Saturn+".

Debug4x includes
emulators that run in MS Windows, but note that it's the legacy
"Hardware Saturn" processor that's emulated, not the ARM processor
and Saturnator. As a result, it's not possible to run anything
that attempts to access the ARM processor or use the new
Saturnator opcodes on the emulators.

Apparently, the firmware ("ROM") for the ARM-based models is
developed (perhaps using an emulator?) using only legacy hardware
Saturn code; and at this point, they will run on the emulators, or
on the calculators themselves, including the hardware Saturn-based
49G. Then selected pieces of code are replaced (presumably to run
faster), and the resulting firmware can be used only on a real
ARM-based calculator.

I'm not familiar with StringWriter, but the built-in 49 series
editor has added features, such as BEGIN, END, COPY, CUT, PASTE,
FIND, and REPLACE. Various editors, notably Emacs, can be
downloaded from hpcalc.org.

Quote:
- Are programs already written (and downloadable) to take
advantage of the ARM processor?

Well, in a sense, all programs that run on the ARM-based models
are running on the ARM processor, although usually through a layer
of emulation, so to some extent, they do "take advantage" of the
ARM processor. Some are available that access the underlying ARM
processor, and perhaps some that use the new Saturnator opcodes.
Also see http://hpgcc.org/ and
http://sourceforge.net/projects/hpgcc.
Quote:
- Is there already a successor programmed yet (HP 51 G?)

The 50g is still pretty new, but I hope that HP is at least
thinking about what to do for its successor. I expect that anyone
who really knows has signed an NDA, so isn't allowed to publicly
comment on this.
Quote:
- What is the future to HP's calculators (compared to other
ClassPad / Nspire)? In other way, will kind of Xpander calculator
show up sometimes in the future?

I don't know. Personally, I'd prefer that HP concentrate on
working on the successor to the 50g, or perhaps a successor to the
35s, or an "updated" release of some other "Classic RPN" model.

Regards,
James


#19

Hi James,

Quote:
The 49 series (49G, 49g+, 48gII, and 50g) have MASD built-in, as part of the "Development Library" application. However, to use mnemonic SysRPL command names, an extable library needs to be installed. Without extable installed, numeric pointers can be used. The extable library supplied by HP includes the supported entry points, and the extable2 library included with Emacs also includes some "unsupported but stable" entry points. You could also make a "customized" extable library with whichever entry points you chose.

With the ARM-based models (49g+, 48gII, and 50g), the Saturn processor is emulated, and includes additional assembly language instructions; this emulated processor is sometimes referred to as the "Saturnator" or "Saturn+".

Debug4x includes emulators that run in MS Windows, but note that it's the legacy "Hardware Saturn" processor that's emulated, not the ARM processor and Saturnator. As a result, it's not possible to run anything that attempts to access the ARM processor or use the new Saturnator opcodes on the emulators.

Apparently, the firmware ("ROM") for the ARM-based models is developed (perhaps using an emulator?) using only legacy hardware Saturn code; and at this point, they will run on the emulators, or on the calculators themselves, including the hardware Saturn-based 49G. Then selected pieces of code are replaced (presumably to run faster), and the resulting firmware can be used only on a real ARM-based calculator.

I'm not familiar with StringWriter, but the built-in 49 series editor has added features, such as BEGIN, END, COPY, CUT, PASTE, FIND, and REPLACE. Various editors, notably Emacs, can be downloaded from hpcalc.org.


That is perfectly clear, thanks for this long answer.

I'm not personaly keen on using StringWriter, it's only because it's much quicker than my HP 48SX text editor!

The built-in editor your describing is just fine. As said before, coming from a 2Mhz calculator, every program will be fast enough for me.

Quote:
Well, in a sense, all programs that run on the ARM-based models are running on the ARM processor, although usually through a layer of emulation, so to some extent, they do "take advantage" of the ARM processor. Some are available that access the underlying ARM processor, and perhaps some that use the new Saturnator opcodes. Also see http://hpgcc.org/ and http://sourceforge.net/projects/hpgcc.
I meant "natively" programmed for the ARM processor (using C or assembly language in that case).

I visited HPGCC's web site, but it doesn't propose programs to run on the HP 49 series, just the C compiler.

Quote:
I don't know. Personally, I'd prefer that HP concentrate on working on the successor to the 50g, or perhaps a successor to the 35s, or an "updated" release of some other "Classic RPN" model.
I find the new 35S terrific. I havn't used it yet, but it realy has the HP look. So a successor to the HP50G using the same look philosophy is fine!

#20

Quote:
I meant "natively" programmed for the ARM processor (using C or
assembly language in that case).

I haven't heard of any written in ARM assembly language, but try
some searches of hpcalc.org for C language programs for the 50g
(or the 49g+, which should also work on the 50g), or ask on
comp.sys.hp48.
Quote:
I visited HPGCC's web site, but it doesn't propose programs to run
on the HP 49 series, just the C compiler.

Won't the compiler allow you to write your own C language programs
for the ARM-based models?

Regards,
James

#21

Some more questions:

HP 48SX

- What is the instruction to display the ROM version?

- Can I use a card without merging it to local memory, and execute a program saved on this card?


HP 71B

- What is the instruction to display the ROM version?

- Where can I find a list of entry points?


Thanks,

Chris


#22

Quote:
HP 48SX
- What is the instruction to display the ROM version?

There are various methods of finding the ROM version of a 48SX/S:
  1. The SysRPL command VERSTRING returns the "version string" in the
    form "HPHP48-A", where the last letter represents the ROM version.
  2. In the 48 series only, the address of the VERSTRING command is
    #30794h, so in UserRPL,
    #30794h SYSEVAL
    returns the version string.

    Caution: Be sure to use the correct address, including the
    trailing h, unless you're willing to lose all user memory.

  3. Transfer any object to a PC in binary mode, and open the file with
    a text editor. The version string is used as the "binary transfer
    header", that is, the first eight bytes of the file.
  4. For the 48SX/S only:
    Hold down the ON key, press and release the D
    key, release the ON key; this starts the "interactive self-test".

    Press the backspace key; this starts the "memory scanner" at
    address 705D9, showing the address and sixteen nibbles of memory
    starting at that address as:

    705D9:1B8DA178E5A111B6
    Press EVAL to execute this particular address, briefly displaying
    a version and copyright message in the form:
    Version HP48-A
    Copyright HP 1989
    If you want to see the message again, just press EVAL again.

    Caution: Don't try to execute any other address, unless you're
    willing to lose all user memory.

    To return to normal operation (at any point in the above), invoke
    a warmstart: Hold down the ON key, press and release the C key,
    release the ON key.

Of course, starting with the 48G series, the UserRPL command
VERSION is available, but the VERSTRING methods can still be used,
and may be used for distinguishing the 48SX/S (versions A-J) from
the 48GX/G/G+ (versions K-R).
Quote:
- Can I use a card without merging it to local memory, and execute a program saved on this card?

Yes, with a "free" RAM card, (not "merged" with system RAM), you
can execute a program stored on the card.

Well, actually, the program will be stored on the card within a
named "backup object" or using different terminology, as a "port
variable", and for execution, it will be copied to a temporary
memory location within system RAM, but that's pretty much
transparent to the user.

Regards,
James


#23

PS:

You might want to see http://www.hpcalc.org/search.php?query=FAQ+Schoorl and http://www.hpcalc.org/hp49/docs/faq/.

#24

Hi again, Chris:

Chris posted:

    "HP 71B - What is the instruction to display the ROM version?
    Where can I find a list of entry points?"

      The ROM version is displayed by simply executing the VER$ command, like this:

         >VER$

      HP71:2CDCC HPIL:1B MATH:1A STRU:A RCPY:E

      This tells you that your HP-71B comes with four internal
      ROMs (ROM1, ROM2, ROM3, ROM4) and their versions are
      2C,2D,2C, and 2C, respectively. This particular HP-71B also had
      the HP-IL ROM plugged in (version 1B), a Math ROM (version 1A)
      and two LEX files, STRU (version A) and RCPY (version E).

      As for the entry points, all of them (lots and lots) are listed in Volume 2 of the Internal Design Specification (IDS).

      Volume 1 discusses the internals of the HP-71B system and data structures in detail, and Volume 3 is the commented assembler source code for all 4 internal ROMs. They are available in this very Museum of HP's DVD. If you're interested in assembly programming for the HP-71B, these volumes are an absolute *must*, period.

Best regards from V.


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