3 replies to this topic

[Andrew Re]

If previously working code starts behaving funny because it's moved to a different ROM location, could that have something to do with the 1 cycle penalty for crossing a page? It's hard to tell exactly what's happening but at a glance the wrong byte is written to GRP0 when it should be erased with a zero. Moving the data used by the kernel to after the kernel solves the bug. I just want to ask if anyone has seen a problem like this before getting down to the nitty-gritty of following the debugger.

[Rybags]

That could do it.

Inadvertantly coding direct addresses instead of using labels or setting up z-page pointers using part of the address rather than high/low byte of a label can break stuff too.

Moving the code but keeping the low byte of the address the same should keep the cycle count the same though.

[GroovyBee]

How about posting the snippets of code that have the problem and a map file (symbol table) so that we don't have to guess .

[Andrew Re]

Thanks for the responses. I'm gonna hold off on looking into this further since my kernel logic is now causing a few problems...