* = $800
LDA #$00
STA $FFFE
LDA #$09
STA $FFFF

LDA #$10
STA $FFFA
LDA #$09
STA $FFFB

LDX #$0
loop:
INX
CPX #$F0
BEQ clear_x
JMP loop

clear_x:
LDX #$0
JMP loop



* = $900
INC $10
RTI

* = $910
INC $20
RTI