Debug output from Amiga code?

[girv]

I'd like to get debug text output on the FSUAE console/log from Amiga side code, with minimal cost on the Amiga side. Ideally it would be something like Amiga code setting up RawDoFmt-style arguments and triggering something on the host side to format and output them.

The Amiga code would be a game, running without the OS, so using the usual library functions or squirting stuff down the serial port isn't possible and/or fast enough to not disturb the Amiga side.

I believe patched versions of WinUAE exist with this kind of feature but I've not found anything for FSUAE.

I've seen mention of lua scripting that might help, but I can't find any guides or examples, only a few years-old snippets.

Open to suggestions...

[jbl007]

I'm not sure what the primary goals of the lua shell were but it was later used to control the emulator, not to debug the running software.
http://eab.abime.net/showthread.php?t=76800
https://lallafa.de/blog/2015/04/a-lua-shell-for-fs-uae/

Perhaps this is more helpful for you:
https://lallafa.de/blog/2016/09/libt...er-for-fs-uae/

or that:
https://github.com/cnvogelg/ucon
https://github.com/cnvogelg/fs-uae/tree/ucon

[deimos]

Originally Posted by girv

I believe patched versions of WinUAE exist with this kind of feature but I've not found anything for FSUAE.

You mean something like the way Bartman's VSCode / WinUAE works, but for FS-UAE?

__attribute__((noinline)) __attribute__((optimize("O1")))
void KPrintF(const char* fmt, ...) {
	va_list vl;
	va_start(vl, fmt);
	long(*UaeDbgLog)(long mode, const char* string) = (long(*)(long, const char*))0xf0ff60;
	if(*((UWORD *)UaeDbgLog) == 0x4eb9 || *((UWORD *)UaeDbgLog) == 0xa00e) {
		char temp[128];
		RawDoFmt((CONST_STRPTR)fmt, vl, PutChar, temp);
		UaeDbgLog(86, temp);
	} else {
		RawDoFmt((CONST_STRPTR)fmt, vl, KPutCharX, 0);
	}
}

[girv]

Originally Posted by deimos

You mean something like the way Bartman's VSCode / WinUAE works, but for FS-UAE?

Kind of, yes, but with the format part happening on the host side as well.


I was thinking lua because it looks like it can trap or at least examine the Amiga memory. Something like the Amiga code loads known addresses with a "command" value and some parameters in just a couple of 68k instructions, then the lua side detects that and performs the "command" (eg: logging a printf string).

[girv]

Originally Posted by jbl007

I'm not sure what the primary goals of the lua shell were but it was later used to control the emulator, not to debug the running software

I meant the base lua scripting built in to FSUAE. How does it work? What can it do?

[girv]

FWIW, I ported the 0xbfff00 debug output and on-the-fly warpmode switching (any config setting really) from WinUAE to my local build of FS-UAE quite easiy.

[sikosis]

Would you care to share how you did this? I'd like to be able to debug when using FS-UAE

[girv]

I just copied the relevant code from WinUAE and recompiled.

I updated this patch to work off the current FS-UAE master at commit bfa0c752:
https://gist.github.com/johngirvin/5...4caed91daf7b7f

You'll see it just does a fprintf at the end of debug_sprintf_do instead of a write_log ... you may want to change that.

The code came from WinUAE so I guess the patch could be merged to FS-UAE without any issues.