Flow control arrangement for the transmission of data packets to a communication network

A packet data bus interconnecting a plurality of data transmitting and receiving devices via a plurality of interfaces where each interface controls bus access for the transmission of data packets over said packet data bus from a group of associated devices to said network, a method for controlling the flow of data packets through said interface to said packet data bus, wherein said method comprises the steps of:

• monitoring an interface buffer to detect when said interface buffer contains insufficient space to accommodate a specified maximum length data packet transmitted from any one of said group of devices associated with said interface;
• generating a jam signal when said interface buffer contains insufficient space to store a next transmitted maximum length data packet;
• and
• applying said jam signal to said group of devices to inhibit any further transmission of data packets from said group of devices.

A packet data bus interconnecting a plurality of data transmitting and receiving devices via a plurality interfaces where each interface controls bus access for the transmission of data packets over said packet data bus from a group of associated devices, a method for controlling the flow of data packets through said interface to said packet data bus, wherein said method comprises the steps of:

• identifying an occurrence or non-occurrence of data transmission activity from at least one of said devices associated with said interface;
• monitoring available space in an interface buffer to determine sufficient or insufficient space in which to store a specified maximum length data packet;
• activating a defer transmission state at all of said devices associated with said interface during a non-occurrence of data transmission activity from any of said devices associated with said interface when said interface buffer is determined to have insufficient space in which to store said maximum length data packet thereby preventing further data transmissions from said devices associated with said interface;
• activating a collision transmission state at all of said devices associated with said interface during an occurrence of data transmission activity from at least one of said devices associated with said interface when said interface buffer is determined to have insufficient space in which to store said maximum length data packet thereby terminating said occurrence of said data transmission;
• switching to said defer transmission state to prevent further data transmissions from said devices associated with said interface in response to the occurrence of said termination of said data transmission;
• and
• deactivating said defer transmission state at said devices associated with said interface when said interface buffer is determined to have sufficient space in which to store said maximum length data packet thereby enabling further data transmissions from said devices associated with said interface.