Tools for patching P59 code

[NSFW]

I typically find either running a debugger to step through code and see where the stack is, or even outputting a debug message to the communication line helps with validating how much space is being taken up.

Have you done that with M68k code? If so, what debugger did you use?

[antus]

I think to debug a PCM over BDM you'd need a motorola spec BDM interface. There are open source designs available, but they generally bit bang from an old school parallel port and probably wont work with USB parallel emulation. There are some commercial USB options, but not cheap. You'd also need to patch the OS to disable the watchdog and update checksum and flash it back. I had to do this to get BDM talking to my E54 (no, I was not able to get re-flash over BDM working on E54 in the end). viewtopic.php?p=132511#p132511

[Tazzi]

Have you done that with M68k code? If so, what debugger did you use?

My testing has been with newer PPC ECUs (non VPW based), so I have not had the need for the older M68K.

In saying that, I know Li from USBJtag has demonstrated previously being able to peek/poke/step and control via BDM on a M68K. I am not sure if he ever implemented an option to implement a breakpoint style setup, but Id guess this could be a possibility to implement for him.

Most of the time, I will only use a JTAG/BDM/debugger interface to get register values when entering into a specific function for R&D or to dump RAM at a specific stage to identify areas in use.

[usbbdm]

If anyone needs debug feature please contact me and I will what I can do for you.

[antus]

Its probably a big ask but if you can make it work with linux drivers and gdb then I think it'd talk to ida and that would be a huge win.

[AngelMarc]

+1 on the Linux support, just to keep away from windows being required.
can't switch my desktop for other reasons (niche audio stuff), would love to do fedora on my laptop and be able to use all these cool things.
The niche audio stuff is active audio cross over. meaning splitting the audio into highs and lows with software, then putting those on their own channels of a soundblaster so bass has it's own amp. Just a complicated 2.2 setup. If anybody knows how to do that on modern Linux (wayland/pipewire), message me.

[AngelMarc]

For anybody trying to get real deep into it. This is some math I did for the 24x wheel (for my custom ECU).
Somewhere buried in the logic, I bet you'll find these numbers (or a multiple of them). "The per degree" is just that.
RPMTime is one tooth to the next.
Assuming it's based on 720 degrees.

Capturef.PNG

Assuming it's maybe always 360 degrees.

Capturew.PNG

Also shown is microsecond per full rotation.

Just in case this helps anybody figure it out even more.