Issue:
    irq wait 0
    irq 0
are translated as:
    irq(wait, 0)                          # 0
    irq(nowait, 0)                        # 1
wait/nowait are incorrect, should be block or ommited (alt: noblock).
After change:
    irq(block, 0)                         # 0
    irq(0)                                # 1