Method and apparatus for border node behavior on a full-duplex bus

• US 20040037309A1
• Filed: 08/05/2003
• Published: 02/26/2004
• Est. Priority Date: 01/18/2000
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Computer Incorporated (Apple Inc.)
• Inventors: Whitby-Strevens, Colin, Hauck, Jerrold V.
• Granted Patent: US 6,891,848 B2
• Time in Patent Office: Days
• US Class Current: 370/462
• CPC Class Codes: H04L 12/40052 High-speed IEEE 1394 serial bus bus transfer protocol on a daisy chain bus using an embedded synchronisation G06F13/426
• CPC Class Codes: H04L 12/6418 Hybrid transport

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.

Claims

1. 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, a method for determining and communicating the existence of a hybrid 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 said received Self-ID packets do not contain a Speed Code.

2. The method of claim 1, wherein said receiving node retains said presumption until a bus reset occurs.

3. A computer-readable medium containing instructions which, when executed by a computer, determine and communicate 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, by performing 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 said received Self-ID packets do not contain a Speed Code.

4. A device containing instructions which, when executed by a computer, determine and communicate 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, by performing 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 said received Self-ID packets do not contain a Speed Code.