System and method to regulate shut down of power supply by sensing an external device connection, and status of connection

• US 6,848,056 B2
• Filed: 04/29/2002
• Issued: 01/25/2005
• Est. Priority Date: 08/25/1998
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Sato, Keiji, Honda, Hirofumi
• Primary Examiner(s): Browne, Lynne H.
• Assistant Examiner(s): Patel, Nitin C.
• Application Number:
  US10/136,248
• Publication Number:
  US 20020129287A1
• Time in Patent Office: 1,002 Days
• Field of Search: 713/300, 713/310, 713/320, 713/322, 713/324, 713/330, 713/340, 709220-222
• US Class Current: 713/300
• CPC Class Codes: G11B 31/006 with video camera or receiver
• CPC Class Codes: H04N 5/765 Interface circuits between an apparatus for recording and another apparatus
• CPC Class Codes: H04N 5/772 the recording apparatus and the television camera being placed in the same enclosure

Abstract

Disclosed is a signal processing apparatus in which it is possible to obtain a favorable system construction in a case where the main unit of the apparatus and an external device have been connected via a digital interface in the recording standby mode. The signal processing apparatus is capable of constructing a network by being connected to a plurality of external devices. In a case where at least connection to an external device has been sensed when the apparatus is in an operation standby state, power shutdown is restricted to thereby curtail bus reset of the network.

Claims

1. A signal processing apparatus comprising:

an operating member with a first circuit,

a first detector which detects that said operating member is operated and generates a first detection signal;

a second detector which detects that an external device is connected to said signal processing apparatus and generates a second detection signal; and

a power supply device control circuit which controls a power supply device so that a power supply for the first circuit is turned off when the second detection signal is not generated and when a predetermined time has elapsed after the last first detection signal is generated, and a power supply for the first circuit is not turned off when the second detection signal is generated and when the predetermined time has elapsed after the last first detection signal is generated.

2. The apparatus according to claim 1, wherein said operating member includes a plurality of switches.

3. The apparatus according to claim 2, wherein said first detector generates the first detection signal when any one of the plurality of switches is operated.

4. The apparatus according to claim 1, wherein said second detector generates the second detection signal when said signal processing apparatus and said external device are connected with each other by a cable.

5. The apparatus according to claim 1, wherein said second detector generates the second detection signal when a predetermined communication between said signal processing apparatus and said external device is established.

6. The apparatus according to claim 1, wherein said signal processing apparatus and said external device are connected by a digital interface.

7. The apparatus according to claim 6, wherein said digital interface performs a bus-reset operation when said first circuit is turned off.

8. A signal processing method comprising:

a first detecting that an operating member with a first circuit is operated and generating a first detection signal;

a second detecting that an external device is connected to a signal processing apparatus and generating a second detection signal; and

a controlling a power supply device so that a power supply for the first circuit is turned off when the second detection signal is not generated and when a predetermined time has elapsed after the last first detection signal is generated, and a power supply for the first circuit is not turned off when the second detection signal is generated and when the predetermined time has elapsed after the last first detection signal is generated.

9. The method according to claim 8, wherein said operating member includes a plurality of switches.

10. The method according to claim 9, wherein the first detection signal is generated when any one of the plurality of switches is operated.

11. The method according to claim 8, wherein the second detection signal is generated when said signal processing apparatus and said external device are connected with each other by a cable.

12. The method according to claim 8, wherein the second detection signal is generated when a predetermined communication between said signal processing apparatus and said external device is established.

13. The method according to claim 8, wherein said signal processing apparatus and said external device are connected by a digital interface.

14. The method according to claim 13, wherein said digital interface performs a bus-reset operation when said first circuit is turned off.

15. A computer-readable storage medium storing a program which executes the signal processing method according to claim 8.

16. A computer program product which executes the signal processing method according to claim 8.