[计] interrupt mask register, interruption mask register
zhōng duàn píng bì jì cún qì ㄓㄨㄥ ㄉㄨㄢˋ ㄆㄧㄥˊ ㄅㄧˋ ㄐㄧˋ ㄘㄨㄣˊ ㄑㄧˋ