TRANSMISSION AND RECEIVING SYSTEM FOR DATA SIGNAL IN PCM EXCHANGE

PURPOSE:To realize transmission and receiving of data between telephone terminals or a telephone terminal and a central data processing device, by assigning each bit string, which constitutes one time slot on a highway of a PCM exchange, in correspondence to telephone terminals and by these bits. CONSTITUTION:A central processing device CC constituting a PCM exchange assigns time slots T0 and T1 to highways HWX and HWP respectively through leads 3 in respect to a control circuit CNT of a transmitting and receiving circuit XR for the data signal, and a transmitting and receiving circuit XR' for the data signal is controlled similarly. Each time the time slot T0 comes from the control circuit CNT, a 8-bit clock pulse CPX is supplied to counter CT ''8'', and the counted result is given to a multiplexer MPX, and one bit is taken out from each of transmission data lines T0X-T7X from interface adapters ACIA0-ACIA7, and these bits are sent to the highway HWX, and the same operation is performed for every frame. Data is received by the same operation for every time slot T0.