PCM TERMINAL EQUIPMENT WITH FRAME ALIGNER CIRCUIT AND FRAME ALIGNING METHOD

摘要

PURPOSE:To suppress the phase difference error less than a fixed level between the writing input frame signal which secures the matching of synchronization of frame phases and a reading frame signal used in a PCM end office device. CONSTITUTION:A window pulse 81 which becomes active with the prescribed fixed data on the address signal 71 of a counter circuit 7 is generated from this signal 71 which is counted by an internal clock 41 used in a PCM end office device for production of a reading frame signal applied to a frame aligner circuit 9. Then the phase difference between an input signal 2 serving as a multiplex signal applied to a built-in memory of the circuit 9 and a writing input frame signal 3 is monitored together with the pulse 81. If the phase difference is delayed so much to exceed the active period of the pulse 81, the circuit 7 is reset to correct the phase delay of the signal 3 to a reading frame signal 101.