Relay apparatus for relaying communication from CPU to peripheral device

• US 20050132098A1
• Filed: 12/03/2004
• Published: 06/16/2005
• Est. Priority Date: 12/11/2003
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Tateno, Tetsuya, Sonoda, Kazuhiro, Kitani, Kazunari
• Granted Patent: US 7,328,288 B2
• Time in Patent Office: Days
• US Class Current: 710/15
• CPC Class Codes: G06F 13/4291 using a clocked protocol

Abstract

In order to reduce overhead of a CPU, a relay apparatus for relaying communication from a CPU to a peripheral device includes communication information holding sections for holding information required for communication with the peripheral devices inside the relay apparatus; and command holding sections, which are provided adjacent to the communication information holding section, for holding commands used to communicate desired information inside the communication information holding section to the peripheral device. The CPU writes desired information in the communication information holding section and the command holding section inside the relay apparatus by burst-mode communication, and the relay apparatus performs communication with the peripheral devices in accordance with instructions from the command holding section after the writing of the desired information in the communication holding section and the command holding section is completed.

Claims

1. A relay apparatus for relaying communication from a CPU to peripheral devices, the relay apparatus comprising:

a communication information holding section configured to hold information required for communication with the peripheral devices inside the relay apparatus; and

a command holding section, which is provided adjacent to the communication information holding section, configured to hold commands used to communicate desired information inside the communication information holding section to the peripheral devices,

wherein the CPU writes desired information in the communication information holding section and the command holding section inside the relay apparatus by burst-mode communication, and the relay apparatus performs communication with the peripheral devices in accordance with instructions from the command holding section after the desired information has been written in the communication holding section and the command holding section.

2. The relay apparatus according to claim 1, wherein the relay apparatus comprises a plurality of the communication information holding sections.

3. The relay apparatus according to claim 2, wherein the relay apparatus comprises a plurality of the command holding sections.

4. The relay apparatus according to claim 1, wherein the command holding section can be specified from a plurality of addresses.

9. An imaging system comprising:

a CPU;

a relay apparatus according to claim 1;

an optical sensor;

a signal processing circuit configured to process signals output from the optical sensor; and

an optical system for forming light into an image onto the optical sensor.

5. A timing pulse generation device for an optical sensor, the timing pulse generation device having a relay function for relaying communication from a CPU to a peripheral device, the timing pulse generation device comprising:

a communication information holding section configured to hold information required for communication to the peripheral device; and

a command holding section, which is provided adjacent to the communication information holding section, configured to hold commands for communicating desired information inside the communication information holding section to the peripheral device,

wherein the CPU writes desired information into the communication information holding section and the command holding section inside the timing pulse generation device by burst-mode communication, and the timing pulse generation device performs communication with the peripheral device in accordance with instructions from the command holding section after the desired information has been written into the communication information holding section and the command holding section.

6. The timing pulse generation device according to claim 5, wherein the timing pulse generation device comprises a plurality of the communication information holding sections.

7. The timing pulse generation device according to claim 6, wherein the timing pulse generation device comprises a plurality of the command holding sections.

8. The timing pulse generation device according to claim 5, wherein the command holding section can be specified from a plurality of addresses.

10. An imaging system comprising:

a CPU;

a timing pulse generation device according to claim 5;

an optical sensor;

a signal processing circuit configured to process signals output from the optical sensor; and

an optical system for forming light into an image onto the optical sensor.