HP41: Updated RUBIK's / CHESS modules

[Ángel Martin]

(12-28-2017 12:24 PM)mstram Wrote:  It looks like you are XEQ'ing some internal routine in the chess module ?( 21,084).

What does that routine do ?

Is it the code at 651D ?
(I used the V41 edit /info command on the chess module, routine 21 shows 651D)

Mike

p.s. Do you have commented source for the chess module .. that you'd like to share ?

There's nothing fancy about that, 21,084 is just a standard decimal number that defines the data registers range used by the routine. These are where the chess pieces information is stored.

The source code is a long story; I purchased the program in 1982 on private magnetic cards, so it's not open code. What made it very tricky to decode was the fact that it was a LABEL-less program, i.e. must of the GTO/XEQ were pre-compiled so LBL statements were not required. This caused a lot of havoc trying to get it into a ROM format, with proper labels, etc.

The programs in the ROM are not private so you can see the code. You can also COPY them to RAM but as they're very long I don't recommend you do that.

I'll post the updated ROM image in a couple of days, need to do some testing first.

Çheers,
ÁM