Maybe it's just late and I should be sleeping, but...
Some time ago, Andrew wrote:
>I dug up my earlier posting regarding an efficient startup.
>Here's my best...
>
>
> ; CLEARS ALL VARIABLES, STACK
> ; INIT STACK POINTER
> ; ALSO CLEARS TIA REGISTERS
> ; DOES THIS BY "WRAPPING" THE STACK - UNUSUAL
>
> LDX #0
> TXS
> PHA ; BEST WAY TO GET SP=$FF, X=0
>
> TXA
>CLEAR PHA
> DEX
> BNE CLEAR
>
> ; 9 BYTES TOTAL FOR CLEARING STACK, MEMORY
> ; STACK POINTER NOW $FF, A=X==0
How about:
LDX #$FF
TXS
INX ; BETTER WAY TO GET SP=$FF, X=0
TXA
CLEAR PHA
DEX
BNE CLEAR
; 9 BYTES TOTAL FOR CLEARING STACK, MEMORY
; STACK POINTER NOW $FF, A=X==0
; BUT 1 CYCLE FASTER
<Ducks>
Chris...
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