| 摘要 |
A data communication system includes a data bus (1) and a number of nodes (2, 3) connected to the bus (1). Each node (2, 3) is arranged to communicate fixed length data packets via the bus (1). The data packets are assigned different priority levels and each node (2, 3) is arranged to concede access to the bus (1) to another node transmitting a higher priority level packet. Some of the nodes are modified to monitor their respective bus access rates. Each of the modified nodes (2), when its access rate falls below a respective predetermined threshold, transmits a restriction request signal onto the bus (1). The other modified nodes (2) reduce their respective bus access rates in response to the restriction request signal, thereby freeing space on the bus (1) for use by the node (2). |
