> I was using the BNE to save cycles over the JMP and a byte of space.
> But you're absolutely right...I never even thought about absolute indirect
> addressing. Guess I misunderstood your intent. :)
You had my intent right, but I remembered about absolute indirect after I
saw your code, so my intent changed :)
> Heh...trying to save cycles in a time wasting routine!!!! :)
Think of it as "ensuring chronological accuracy" rather than
"time-wasting" :)
> LDA COUNT ; WAIT CYCLES = 16 - COUNT
> LSR A ; SETUP CARRY BIT
> STA $80 ; STORE OFFSET VALUE
> DELAY STA WSYNC
> JMP ($80) ; WASTE 5 CYCLES
> TABLE NOP ; WASTE 2 CYCLES
> NOP ; WASTE 2 CYCLES
> NOP ; WASTE 2 CYCLES
> NOP ; WASTE 2 CYCLES
> NOP ; WASTE 2 CYCLES
> BCC JUMP ; WASTE 2 OR 3 CYCLES
> END ...
>
> During initialization, the address of TABLE should be stored in $80. As is,
> this one should give you a delay of 5 or between 7 and 18 cycles (can't get 6).
> I think. I'm relatively new to cycle counting.
This'd work if TABLE is the first byte of a page, and if $81 is set to the
number of that page (JMP ($xx) uses a 16-bit pointer.) If you can't set
up TABLE that way, you'd need to do an add before storing the offset
(which, of course, screws up the carry you already set...)
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