waits until ly=3
sets lyc to 4
enables lyc int
enables mode2 int
waits for int

on int:
jumps to 0x1000
lots of nops
reads IF
outputs value of IF&3

DMG-08 / CGB:
lycm2int_m2irq_1.gb should output 1
lycm2int_m2irq_2.gb should output 3
