HP-41CL: Suggested module format update

[Christoph Giesselink]

(12-23-2021 02:29 PM)MeindertKuipers Wrote:  I have not tested the V41 beta, I just looked at the ModEdit and played with it a bit, I really like it, much cleaner than my implementation!. Just a few questions:

- a MOD file with multiple ROMs must have all the same MOD types (MOD1 or MOD2) ? No mix?
- what is the maximum number of ROMs in a MOD file? I use this format for MLDL2000 backups, and there can be (in theory) more than 100 ROMS in one MOD file. I now receive a load error when opening such a backup file. Would be good to know your maximum. A MOD file with 12 ROMS works.
- I misuse the MOD1 format for a baclup of the Settigs Registers of the MLDL2000. This also results in a load error in your ModEdit.

As a suggestion, would be nice to have an indication of the 41CL CRC of the image.

(12-20-2021 06:42 PM)Christoph Giesselink Wrote:  A new release of V41 is not planned at the moment, so a public beta version of V41 R9Hb1 supporting the MOD2 format is available at

https://hp.giesselink.com/beta/V41R9Hb1-xmasbin.zip

Caution: Don't start the V41.exe file outside it's installation directory. The environment is missing and so the MOD files are not found which may then removed from the current LOD file!

I tested this feature by converting NUT-CX.mod and HEPAX.MOD to the MOD2 format. NUT-CX.mod contain only read-only modules, whereas HEPAX.MOD contains writable QROM modules which are updated when the session is closed.

Quote:- a MOD file with multiple ROMs must have all the same MOD types (MOD1 or MOD2) ? No mix?

The FileFormat with the MOD type is part of the ModuleFileHeader existing only once in a MOD file. So no mix!

Quote:- what is the maximum number of ROMs in a MOD file? I use this format for MLDL2000 backups, and there can be (in theory) more than 100 ROMS in one MOD file. I now receive a load error when opening such a backup file. Would be good to know your maximum. A MOD file with 12 ROMS works.

The possible no. of pages is normally limited by NumPages in the Header. It's a byte, so the maximum for pages is 255. But ModEdit is a so called dialog based application, where the class members and so the file content are created on the stack. Maybe there's a stack overflow on too many ROM pages.

Quote:- I misuse the MOD1 format for a baclup of the Settigs Registers of the MLDL2000. This also results in a load error in your ModEdit.

Many structure members have for example a byte container, but only limited values like 1 to 4 maybe allowed. To reduce errors on these "free number" fields I mostly use pre defiend combo boxes to limitate the settings.

Maybe you mail one of these MOD files making trouble as example for analysing to me. It should make no difference if the module pages containing true ROM data or fake data filled with anything else for analysing.

Quote:As a suggestion, would be nice to have an indication of the 41CL CRC of the image.

I don't know anything about the 41CL, and so nothing about the 41CL specific CRC. A description and an example file would be welcome.