.p816 .code main: sei stz $4207 ; IRQ at H=0 stz $4208 ; (leave IRQ disable flag set so it only resumes after WAI) lda #%00010000 sta $4200 wai bit $4211 ldx #0 : lda #0 : wai ; go back to sleep bit $4211 ; hit the snooze button sta $2180,x ; hit something else inc bne :- inx bpl :-- stp .segment "BOOT" .addr main