Method of and apparatus for detecting direction of reception of bus packets and controlling direction of transmission of bus packets within an IEEE 1394 serial bus node

A method of transmitting a bus packet from one of a plurality of ports within a node on a bus structure, comprising the steps of:

• a. determining on which port a destination node of a current bus packet is coupled;
• b. transmitting the current bus packet on the port to which the destination node is coupled;
• and
• c. holding ports within the plurality of ports busy, which are not the port to which the destination node is coupled, while the step of transmitting is performed.

A node on a bus structure for receiving and transmitting bus packets to other nodes on the bus structure comprising:

• a. an interfacing circuit for interfacing the node to the bus structure, the interfacing circuit including:
• i. a plurality of ports each configured for coupling to the bus structure, each port having a corresponding direction on the bus structure;
• ii. a determining circuit coupled to the plurality of ports for determining on which port a received bus packet is received, wherein the determining circuit sends information representing the port on which the received bus packet is received with the received bus packet;
• and
• iii. a transmitting circuit coupled to the plurality of ports for transmitting an outbound bus packet on a predetermined one of the plurality of ports while holding remaining ports within the plurality of ports busy;
• and
• b. a processing circuit coupled to the interfacing circuit for determining if the received bus packet was received on a secure port.