--- instance0 ---
controller iteration 0
b'0123'
controller iteration 1
b'0123'
done
--- instance1 ---
target iteration 0
IRQ_END_WRITE 2
bytearray(b'--0123--')
IRQ_END_READ 2
target iteration 1
IRQ_END_WRITE 3
bytearray(b'--00123-')
IRQ_END_READ 3
done