Vehicle communications bus link with state machine

摘要

A link apparatus in a node of a mulitinode, collision-resolution, multiplexing communications system connected between a microcontroller (MCU) and a integrated driver and receiver (IDR) of the node for assuming some of the functions of the MCU in delivering and receiving messages to and from a signal-wire communications bus. The link apparatus provides circuits for automatically prepending a start-of-frame to a message being placed on the bus after determining that the conditions on the bus are suitable for transmitting messages. The link apparatus also contains circuits for determining when a node has won arbitration over another node competing for time on the bus.