waits for ly 141
enables lycint
sets lyc to 143
enables m1 int
d=2
interrupt enable

on lycint:
dec d
if nz jr 1
ret
jump to 0x1000
ei
does a bunch of nops
reads IF
outputs value of IF&3

lycint_m1intirq_1.gb should output 3
lycint_m1intirq_2.gb should output 1