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chitselb / pettil

6502 Forth-83 dialect for the Commodore PET 2001
http://pettil.tumblr.com
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Slightly improved paday ? #85

Open barrym95838 opened 3 years ago

barrym95838 commented 3 years ago

If I understand correctly what's going on, we should be able to save a byte and a couple of cycles here:

paday
    sec             ; A+1 = offset to be added to IP
    adc pip
    bcs paday01
    cmp #$FF
    adc #0          ; (don't allow xxFF to happen)
paday01
    tay
    lda #0
    adc pip+1
    rts