Abstract: A method for determining and communicating the existence of a hybrid bus In a full-duplex communications system having plurality of nodes, wherein one of the nodes is compliant with the P1394b standard and receives a Self-ID packet from the bus, comprising the acts of examining received Self-ID packets by the P1394b compliant node for the absence of a Speed Code; and presuming the existence of a hybrid bus if any of the received Self-ID packets do not contain a Speed Code.

Abstract: A method and apparatus is disclosed for preventing loops in a full-duplex bus. One method has the acts of: selecting at least two candidates to join said bus; establishing a dominant candidate from one of said at least two candidates; testing for loops in said bus; and joining said dominant candidate if no loops are found in said bus. Another method has the acts of: selecting a plurality candidates to join said bus; establishing at least one dominant candidate; testing for loops in said bus; and joining said at least one dominant candidate if no loops are found in said bus. Alternative embodiments are shown that utilize unique identifiers to facilitate candidate selection and to establish dominance on the bus.

Abstract: Various methods for ensuring compatibility between devices utilizing the IEEE 1394-1995 serial bus standard and new implementations of the standard are disclosed. Methods are disclosed which a allow border nodes to speed filter a Legacy cloud. Methods are disclosed which allow a BOSS node to speed filter a Legacy cloud. A method for ensuring compatibility is disclosed which comprises the acts of determining whether the B PHY desires to communicate at a speed on a bus having a peer device not capable of communicating at the speed; and speed filtering the peer device if the B PHY determines that the peer device cannot communicate at the speed. Various data packets and methods for transmitting data packets are also disclosed to satisfy the needs discussed herein.

Abstract: The present invention provides a method for generating random jitter test patterns by generating a sequence of maximum-size asynchronous packets according to the P1394b standard and transmitting the sequence to the device under test. The present invention provides a method for generating jitter test patterns by disabling the transmitter data scrambler of the second device; clearing the port_error register of the device under test; and sending a test pattern to said device under test. The present invention provides for a method for generating supply noise test patterns comprising: transmitting a test pattern to the DUT comprising a maximum length asynchronous packet containing alternate 0016 and FF16 bytes.

Abstract: A method for determining and communicating the existence of a hybrid bus In a full-duplex communications system having plurality of nodes, wherein one of the nodes is compliant with the P1394b standard and receives a Self-ID packet from the bus, comprising the acts of examining received Self-ID packets by the P1394b compliant node for the absence of a Speed Code; and presuming the existence of a hybrid bus if any of the received Self-ID packets do not contain a Speed Code.

Abstract: A method and apparatus relating to the behavior of border nodes within a high performance serial bus system is disclosed. A method for determining and communicating the existence of a hybrid bus is disclosed. A method for determining a path to a senior border node is disclosed, as is a method for identifying a senior border node Various methods for properly issuing gap tokens within a beta cloud are disclosed. A method for returning control to the senior border node is disclosed. A method for determining whether a BOSS node may issue a grant is disclosed.

Abstract: A method for loop breaking includes selecting a first port of a node, transmitting a first packet containing a first identifier from the first port of the node, listening for a second packet containing a second identifier for a period of time on a second port of the node, joining the first port and the node if the second identifier meets a first criteria with respect to the first identifier and quarantining the first port when the second identifier meets a second criteria with respect to the first identifier.

Abstract: A method and apparatus is disclosed for preventing loops in a full-duplex bus. One method has the acts of: selecting at least two candidates to join said bus; establishing a dominant candidate from one of said at least two candidates; testing for loops in said bus; and joining said dominant candidate if no loops are found in said bus. Another method has the acts of: selecting a plurality candidates to join said bus; establishing at least one dominant candidate; testing for loops in said bus; and joining said at least one dominant candidate if no loops are found in said bus. Alternative embodiments are shown that utilize unique identifiers to facilitate candidate selection and to establish dominance on the bus.