Ring interface and ring network bus flow control system

Abstract

A ring interface is coupled to a current node in a ring network having a plurality of nodes and corresponding ring interface for each of said nodes. The ring interface includes a ring input port operative to conduct upstream message packets from a previous node to the ring interface, a ring output port operative to conduct message packets to a next node of the ring network, and a bypass queue operative to buffer message packets. A receive queue buffers message packets before passing them on to the current node. An address filter is coupled to the ring input port to receive the upstream message packets, read their destination addresses and pass them to the bypass queue if the addresses correspond to another node and pass them to the receive queue if their addresses are that of the current node. A transmit queue buffers message packets from the current node and a bypass-transmit queue arbiter is coupled to outputs of the bypass queue and the transmit queue and is operative to select message packets from one of the bypass queue and the transmit queue in accordance with predetermined selection criterion and transmits the selected message packets to the ring output port.