A.格林尼治標(biāo)準(zhǔn)時(shí)間(GMT) B.協(xié)調(diào)世界時(shí)(UTC) C.國(guó)際原子時(shí)(TAI) D.北京時(shí)間
A.SVLD B.PI C.RPIT D.MU
A.IEEE1588 B.PPM C.PPS D.IRIG-B