Interface unit for digital serial data, bridge portal utilizing the same, and a method for transmitting digital data

An interface unit for digital serial data comprising:

• a physical layer section connected to a bus;
• an open host controller interface section connected to a host bus;
• and
• a link layer section inserted between the physical layer section and the interface section,
• wherein a first transmission packet is sent from the interface section to the link layer section, and a second transmission packet is sent from the physical layer section to the bus,
• wherein the first transmission packet at least includes transmission information, transmission end information for identifying whether a transmission end from which the transmission information is transmitted is a self-node or another node residing in another bus, and if the transmission end information indicates that the transmission end is another node, further includes identification information about another node, and
• wherein the second transmission packet at least includes transmission information, and node information about a transmission end from which the transmission information is transmitted, and uses identification information about a self-node as node information about the transmission end when the transmission end information included in the first transmission packet indicates that the transmission end is a self-node, while uses identification information about another node included in the first transmission packet when the transmission end information indicates that the transmission end is another node.

A bridge portal constituting a bridge for connecting a plurality of buses, comprising:

• a physical layer section connected to the bus,
• a host controller interface section connected to a host bus;
• and
• a link layer section inserted between the physical layer section and the interface section,
• wherein a first transmission packet is sent from the interface section to the link layer section, and a second transmission packet is sent from the physical layer section to the IEEE 1394 bus, wherein the first transmission packet at least includes transmission information, transmission end information for identifying whether a transmission end from which the transmission information is transmitted is a self-node or another node residing in another bus, and if the transmission end information indicates that the transmission end is another node, further includes identification information about another node, and
• wherein the second transmission packet at least includes transmission information, and node information about a transmission end from which the transmission information is transmitted, and uses identification information about a self-node as node information about the transmission end when the transmission end information included in the first transmission packet indicates that the transmission end is a self-node, while uses identification information about another node included in the first transmission packet when the transmission end information indicates that the transmission end is another node.