notes.txt

Here are some general notes you should know when programming:

==[68000]=======================================================================
"Most assemblers accept DBRA for DBF for use when only a count terminates the
loop (no condition is tested)." - M68000 Family Programmer's Reference Manual

This includes vasm and whatever assembler SNK was using.

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Some of the optimizations made by compilers can possibly break your ROM.
This is why the freemlib examples currently use vasm's -devpac parameter, as it
is known to produce working ROMs. (Of course, it might be possible to disable
certain optimizations, but this hasn't fully been looked into.)

==[Z80]=========================================================================
If you happen to be writing both Z80 and 68K code, you'll probably either know
this or will need to remember it: source and destination registers are typically
flipped between the two architectures.

e.g. Loading an 8-bit value from one register to another:
(68K) move.b source,dest
(Z80) ld     dest,source