>It's surprising how often in 6502 programming, it is better to keep data in
>memory than in registers. That is good since there are so few registers.
Yeah, but it's completely opposite from 80x86 programming, where you've got
at least six 16-bit registers, four of which you can access the high and
low bytes separately, and more if you know what you're doing (up to seven
32-bit registers, a couple 16-bit regs, and some floating-point storage on
the 386+), and the #1 rule is keep everything in the registers. Compare
this to three 8-bit registers plus the stack register if you know how to
use it.
I miss having MUL and DIV instructions =) Also, exactly which instructions
set and clear the carry? I know the shifts and rotates do, and ADC is
obvious, but what exactly do SBC and the compares do to the carry?
>>My code had Y zeroed from a DEY/BNE loop before the LDA that I needed, so I
>>was trying to capitalize on that and failed =) I'm going to need to use
>>LDY $80 / LDA $00,Y (the one combination you didn't mention).. thanks again
>>for the help.
>
>There is no Zero Page,Y although there is an Absolute,Y so you could
>conceivably do LDA $0000,Y and only take one more byte and no more cycles.
>I think the assembler will make this adjustment for you in most cases.
No ZP,Y? My reference says there is and I've used it a number of times
already.. I guess DASM already adjusted it to Absolute,Y for me.
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