[Coco] Need some tips debugging 6309 for OVCC

[Robert Gault]

Walter,

What did you mean by EOU and MESA? Are they typos for EQU and MESS?

There is no 6309 code in NitrOS-9 Merge nor does there seem to be any special use of the stack that might cause problems going from 6809 to 6309 code.

One way to use the debug/trace facility in MESS/MAME to trouble shoot this problem might be to assemble a special version of Merge with a continuous loop
loop bra loop
so you can in debug mode you can step over the loop and see how Merge is failing.

Robert

 On Tuesday, December 3, 2019, 7:01:26 PM EST, Walter Zambotti <zambotti at iinet.net.au> wrote:


 Curtis

It manages to boot completely and setup 3 other windows.  It even creates the vterm window successfully.  The only thing causing the crash is the merge command that is loading the fonts.

I would assume this would cause the graphics driver to kick into gear.  So if I avoid any graphics I seem to be ok.

I've even run basic09 (6309) and tried some simple division and multiplication math. Seems ok!

I have now looked at MAME 6309 code and it is basically an abstraction layer to a general purpose device emulator within MAME. There is no chance of extracting the 6309 cpu component and running it independently of MAME.

So I will not be able to compare the MAME 6309 cpu to the VCC or OVCC 6309 cpu.

I now have to identify the culprit instructions!

Walter