[计] PABX, private automatic branch exchange

zhuān yòng zì dòng jiāo huàn fēn jī ㄓㄨㄢ ㄩㄥˋ ㄗˋ ㄉㄨㄥˋ ㄐㄧㄠ ㄏㄨㄢˋ ㄈㄣ ㄐㄧ