HP-41 instruction print bug found

[Ángel Martin]

I've followed this discussion with interest, and if I understand well at the crux of it is the inability by the OS to handle some corner cases of prompting functions in plug-in ROMS, is that correct?

We know those are not supposed to be supported (HP dixit) , but I also use them profusely in my advanced modules, including the IND case, and have never encounter any glitches (ok, the printer case I have no experience with, I rarely use a printer in my system anyway).

For example in the WARP_Core module there are a dozen or so of functions used to access register's contents replacing the native RCL/STO. They can happily handle IND and IND ST, and that for all status registers as well.

You're right this is not done using the internal OS routines, which were not designed to do that (regardless of their apparent ability using the function's name characters to make them prompting) - and that's why the module handles all the prompting in dedicated subroutines (some stubs also in the Library#4 BTW), not using calls to the OS.

The upside is that the same prompting handling routines work for sub-functions as well not only for the main FAT, and that's a big plus.