.define TestFFh ! This subroutine tests if the value on top of the stack is <= 256. ! It is used if the istruction argument is on top of the stack. ! The value is saved in Y. TestFFh: cmp #2 bpl 1f ! value > 256 cmp #0 beq 2f cpx #0 bne 1f ! value is zero 2: dex txa tay rts 1: ldx #Eoddz lda #0 jsr Trap