> Here's a way to implement single cycle resolution without the use of the
> carry flag (which adds overhead in the setup and at the end):
>
> ; A is assumed to hold the delay value plus the offset address of JumpTable.
> ; Or, you can align JumpTable to a page boundary.
>
> sta indjmp
> jmp (indjmp) ; point indjmp+1 to JumpTable somewhere in your init code
>
> JumpTable:
> dc.b $C9
> dc.b $C9
> ; repeat as many $C9's as you need for the maximum number of cycles you
> ; you need to delay by.
> dc.b $C9 ; opcode: CMP immediate (4 cycles: uses the $C5, executes
> ; the NOP below.)
> dc.b $C5 ; opcode: CMP zero page (3 cycles, uses up the NOP as a
> ; destination address of $EA)
> nop ; opcode: NOP (2 cycles by itself)
That's... incredibly wizardly. But isn't something backwards? The way I
see it, won't a larger value in the accumulator cause it to jump farther
into the table, skipping more instuctions and delaying fewer cycles?
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