compilable in x816, and written in under 30 seconds!

.mem 8
.index 8
.opt on
.org $8000

reset ;---
lda #$ff
sta $4015
sta $4000
sta $4001
sta $4002
sta $4003

hello ;---
jmp hello

irq ;---
nmi ;---
rti

.pad $fffa
.dcw nmi
.dcw reset
.dcw irq