If you look at a 6502 instruction chart, looking at the patterns and adjacent opcodes, you'd expect to see "STX abs,Y" at 0x9E. But it's not there.
Instead, you get an illegal instruction that is kind of like "STX abs,Y", except it *sometimes* stores a different value instead (it will AND the value stored with the high byte of the address, but not always). It's called "SHX abs,Y".
Is PPU_DATA read slow?
Moderator: Moderators
Re: Is PPU_DATA read slow?
Here come the fortune cookies! Here come the fortune cookies! They're wearing paper hats!
Re: Is PPU_DATA read slow?
...does that stand for SHit up X?
Re: Is PPU_DATA read slow?
Store H bitand X, but ... effectively, yes, the cuss words.
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