SERIAL TRANSMISSION APPARATUS, INFORMATION PROCESSING APPARATUS, AND SERIAL TRANSMISSION METHOD

• US 20120093211A1
• Filed: 10/11/2011
• Published: 04/19/2012
• Est. Priority Date: 10/15/2010
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: OGAMI, Shogo, SHIRASE, Kenji, NEGISHI, Tatsuhiko
• Granted Patent: US 8,880,972 B2
• Time in Patent Office: Days
• US Class Current: 375/224
• CPC Class Codes: H04L 1/1874 Buffer management
• CPC Class Codes: H04L 1/188 Time-out mechanisms
• CPC Class Codes: H04L 2001/0093 Point-to-multipoint
• CPC Class Codes: H04L 47/283 in response to processing delays, e.g. caused by jitter or round trip time [RTT]

Abstract

A serial transmission apparatus, which transmits data through a serial communication line, includes a transmission unit configured to transmit data stored in a transmission data buffer to a transmission destination apparatus, a time-out detector configured to detect a time out when a response to the transmitted data from the transmission destination apparatus is not received within a specified period of time, a recovery state detector configured to detect a recovery state representing that the serial communication line is in a link recovery process, and a retransmission request unit configured to request the transmission unit to transmit again the data which has been stored in the transmission data buffer when the time-out detector detects the time-out or when the recovery state detector detects the recovery state of the serial communication line.

Claims

1. A serial transmission apparatus which performs data transmission through a serial communication line, the serial transmission apparatus comprising:

a transmission device to transmit data stored in a transmission data buffer to a transmission destination apparatus;

a time-out detecting device to detect a time out when a response to the transmitted data from the transmission destination apparatus is not received within a specified period of time;

a recovery state detecting device to detect a recovery state representing that the serial communication line is in a link recovery process; and

a retransmission requesting device to request the transmission unit to transmit again the data which has been stored in the transmission data buffer when the time-out detecting device detects the time-out, or when the recovery state detecting device detects the recovery state of the serial communication line.

2. The serial transmission apparatus according to claim 1, further comprising:

an abnormality-notification transmission device to generate abnormality notification used to notify the transmission destination apparatus of detection of the recovery state of the serial communication line detected by the recovery state detecting device and causes the transmission device to transmit the abnormality notification.

3. The serial transmission apparatus according to claim 1, wherein the recovery state detecting device detects the recovery state when a signal representing a link state of the serial communication line denotes the recovery state.

4. An information processing apparatus comprising:

a processor;

a memory configured to be connected to the processor through a bus; and

a serial interface configured to transmit data to another apparatus through a serial communication line and configured to be connected to the processor and the memory through the bus,

wherein the serial interface includes

a transmission unit configured to transmit data stored in a transmission data buffer to a transmission destination apparatus,

a time-out detector configured to detect a time out when a response to the transmitted data from the transmission destination apparatus is not received within a specified period of time,

a recovery state detector configured to detect a recovery state representing that the serial communication line is in a link recovery process, and

a retransmission request unit configured to request the transmission unit to transmit again the data which has been stored in the transmission data buffer when the time-out detector detects the time-out, or when the recovery state detector detects the recovery state of the serial communication line.

5. A serial transmission method for performing data transmission through a serial communication line using a serial transmission apparatus, the serial transmission method comprising:

transmitting data stored in a transmission data buffer to a transmission destination apparatus;

detecting a time out when a response to the transmitted data from the transmission destination apparatus is not received within a specified period of time;

detecting a recovery state representing that the serial communication line is in a link recovery process; and

requesting the transmission unit to transmit again the data which has been stored in the transmission data buffer when the time-out detector detects the time-out, or when the recovery state detector detects the recovery state of the serial communication line.

6. A serial transmission method for performing data transmission through a serial communication line using a serial transmission apparatus, the serial transmission method comprising:

receiving data transmitted through the serial communication line;

detecting a recovery state representing that the serial communication line is in a link recovery process; and

transmitting an abnormality-notification indicating abnormal condition to a destination apparatus when the time-out detector detects the time-out, or when the recovery state detector detects the recovery state of the serial communication line.