MSX Frogger - early musing

[Steve Nickolas]

So I just (with the help of a disassembly assisted by both IDA and MAME)
ported Frogger from the MSX to the Nabu (same CPU, VDP, PSG).

As there are a few cards for the Apple ][ that have the TMS9918 and
AY8910, I've thought about what may be easiest or hardest to port. The
main issue being, it's mostly Z80 stuff.

I've reworked Frogger so that it (theoretically; I haven't tested it on
metal) should 100% work on the Nabu; if one can translate the Z80 code to
6502, using the Nabu port as notes on where the hardware-specific stuff
is, perhaps it can be adapted to the Apple ][ with a sprite card.

-uso.