| 摘要 |
<p>The subscriber line interface modem is for use in a telecommunications system line interface module which also includes subscriber signalling and switching circuits and a control microprocessor. The modem comprises bus interfacing means, channel means and clock supply means. The interfacing means receives address data and control information from the microprocessor and despatches address, data and control information to the microprocessor for evaluation. The channel means includes a non-return to zero/conditional diphase modulation (NRZ/CDM) conversion means which receives NRZ coded information from the circuits and despatches CDM information to the subscriber line. A CDM/NRZ conversion means receives CDM information from the subscriber line and despatches NRZ coded information to the circuits. The processing of information through the modem is controlled by the microprocessor in conjunction with the clock signals generated by the clock supply means.</p> |
