APPARATUS FOR INTERFACING DATA LINK SPEED BETWEEN DIFFERENT SIGNAL SYSTEMS

摘要

The apparatus is fit for realizing level one function of 7-class open layer system for data communication protocol of ISDN exchange system. The apparatus includes a time switch interface unit (37) for receiving 2MCLK and FS signal of a time switch and for transmitting data having speed of 2.048 Mbps to a time switch, a bit speed changer (51) for changing 64 Kbps or 56 Kbps data up to 2.048 Mbps, and for vice-versa, a parity code checker (52) for inserting parity or detecting parity bit, an error detection circuit (53) for detecting error of 2MCLK and FS signal, a data channel interfacing unit (56) for enabling a terminal or a protocol chip to receive or to transmit 64 Kbps and 56 Kbps, and a loop back controller (55) for detecting error of link.