[atari] Optimize findfreeiocb #337
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mysterymath
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Jun 14, 2024
| bcc loop | ||
| inx ; return ZF cleared | ||
| adc #$10 ; C = 0 | ||
| bpl loop |
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This should have a comment explaining why bpl gives the loop termination condition, now that it's no longer an explicit compare against #$80.
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What's your point? Checking the N flag is the 6502's idiomatic way to determine $00-$7F vs $80-$FF. It's the cmp #$80 that looked strange.
Also, all Atari programmers should be aware that there are 8 IOCBs.
I'm okay with adding a comment, but I don't know what should it explain?
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The significance of 0x80. It's looping through the IOCBs, each of which are 0x10 bytes long, and there are 8 of them. I've done some Atari programming, but I didn't have either of those two facts memorized.
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