>12 cycles (3Bytes):
>
>JSR AnyRTS
>
>14 cycles and more
>
>- jsr to any subroutine point wasting the desired # of
>cycles without destroying other data.
>
>Or do something like:
>
>...
>Waste16
> NOP
>Waste14
> NOP
>Waste12
> RTS
Yup, good point though I've kinda been focussed on the <10 cycles to maximise a bytes/cycles ratio (least bytes, most cycles..) since usually it's for timing in the display kernal (spacing RESP0's or altering other TIA registers at appropriate times). A good variant where the length of the pause is variable is::
jmp ($ZeroPage)
nop
nop
nop
(Whole bunch of NOPs)
Where the value in $ZeroPage is an address down the list of NOPs depending upon the length of the pause. Much more usefull on a CPU with 16-bit registers so you can determine (add) the address quickly but could still be usefull... There's a little bit of overhead to setting it up (The jump and whatever adc type instructions you need) but you have a much higher degree of cycle count accuracy for "long" pauses than a loop like:
ldy $ZeroPage
NextPause:
dey
bne NextPause
gives you. (The "resolution" of the loop pause is 4 cycles, the jmp () pause is 2 cycles...)
Chris...
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