GRAPH-LEX 71

[jsi]

The JPC ROM REV E contains functions of a GRAPH-LEX71 graphic module for the HP-71, which originated from BCMW Informatique Paris, see the JPC ROM Page.

The sources of the graphics module were never released. J-F Garnier did some disassembly. I continued the work to an extent, that I could build a stand-alone LEX and ROM file of that module.

Interestingly, most of the functionality was implemented as a poll handler. It was possibly intended to extend the module with support for other devices by adding additional LEX files.

The module has some simple graphic commands. They create a raster graphics file with the fixed name "graphile" and a custom file type. This file can be dumped to a ThinkJet printer, which is the only output device supported by that package.

Please find enclosed a zip file with the following content:

• Assembler source files of the module
• Build file bldgra.sh (linux) to create the module either as LEX or ROM file
• User documentation (BMCW)
• LIF image file GRA71.DAT with the LEX and ROM files and two small Basic test programs
• PDF file with sample output of the test programs
  

You need either a "real" ThinkJet or the emulated ThinkJet in pyILPER to obtain the output.

Regards
Joachim

[J-F Garnier]

Great attempt to rebuild the "GRAPHIC module" for the HP-71B !
I didn't work on this part of code since 2006 !

Indeed the LEX is based on the poll handler mechanism, and so could be expanded to support other types of graphics devices, such as HP-GL plotters or graphics displays.

Actually, one reason why I didn't go so far in the poll handler code disassembly and documentation is that, at the time, I had the project to rewrite this part for an HP-GL plotter. I have a special relation with HP-GL, for reasons that the readers of my article in the RCL 40 book will understand.

I gave up with this project, that would have been fairly complex since the poll handler interface is not documented, and the interest is finally very limited for me, I don't have any HP-GL compatible devices to drive.

J-F

[J-F Garnier]

Stimulated by the recent release of the JPC ROM E source files, I dug in my archives and found a binary image of the original (well I assume it's the original) standalone "GRAPHIC module" for the HP-71B.
The VER$ version returns "GRPH:A RSTR:B" in line with the corresponding VER$ description in the JPC ROM E gdef.as file.
We can interpret this VER$, at the light of the JPC ROM E source files, as the versions of the main graphic module (GRPH) and raster driver (RSTR).

An interesting exercise would be to reconstruct the standalone "GRAPHIC module" source files, maybe are there some hidden features to discover, but I will not do it in the short term (other on-going projects).

Attached is the ROM image for emulators.

J-F