HP-41CL: Suggested module format update

[hth]

This is for anyone making tools for the HP-41.

As you probably know there are two common ways to deal with HP-41 plug-in page images, module files (.mod extension) and ROM files (.rom extension).

Normal HP-41 page data uses 10-bit words, but for the 41CL we have 16-bit words. The upper bits are used for speed annotations, making timing loops run at the normal speed regardless of any turbo mode. Modules that contain such timing annotations cannot be represented by the module format and is lost.

I propose that there should be a variant of the module format that does not pack the data, but instead stores it as 16-bit data internally (like in the .rom format).

To implement this I have updated my own tools to have a MOD2 variant (the current one is MOD1). The only other difference is that it stores page data unpacked in the same way as .rom files.

I talked to Warren about this and he agrees that this is a solution to the problem. I suggest that anyone making tools to consider it.

Comments are welcome.