| 摘要 |
A message communication system (12) for receiving, storing and transmitting messages comprises RAM-based storage buffers (20, 22) having two parallel ports (18, 44) and two serial ports (19, 17) and an serial output portion (15) which has an input for receiving messages and an output for transmitting messages. The two serial ports (17, 19) and one of the parallel ports (44) are coupled to the serial output portion (15). Each message comprises ID information and data, the ID information of each message providing an indication of the priority of each message. The serial ports transfer serially the ID bits of the transmitted and received messages between the serial output portion (15) and the storage buffers (20, 22). Logic (28) is used to determine, from the ID bits, which message of the messages to be transmitted has the highest priority and to provide the ID bits of the highest priority message serially to serial output portion (15). Additional logic (48, 50) receives the ID bits of the received messages serially from the serial output portion (15) and determines whether the messages are to be stored in the RAM-based storage buffer, by comparing the received ID bits with previously stored ID bits. <IMAGE> |
