DATA COMMUNICATION CIRCUIT OF THE FIELD BUS INTERFACE BOARD

摘要

The data communication circuit supports digital serial communication between interface board of a personal computer and twisted pair cable of field bus. The data communication circuit includes a Manchester encoder/decoder (2) for generating encoder and decoder clock signal according to the control signal transmitted from a CPU and for encoding and decoding I/O data signal, a latch/shift register (3) for converting 8 bit parallel data of a CPU (1) to 1 byte serial data to transmit parallel data to the encoder/decoder (2) and for converting 1 byte serial data comins from the encoder/decoder (2) to 8 bit parallel data, a CRC generator (4) for generating CRC check frame and for checking data transmission error, and a driver/receiver (5) for driving and receiving data between the Manchester encoder/decoder (2) and field bus.