Device, operation-mode control method, and recording medium

Patent metadata

Field	Value
Publication number	US-10310592-B2
Application number	US-201615336283-A
Country	US
Kind code	B2
Filing date	Oct 27, 2016
Priority date	Nov 2, 2015
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

A device has a plurality of power states. The device includes: a communication processor configured to communicate with a communication destination device connected via a cable; a confirmation-signal receiver configured to receive a connection confirmation signal that is transmitted if being connected to the communication destination device via the cable; a contoller configured to determine a power state depending on whether the confirmation-signal receiver receives the connection confirmation signal; and a power circuit configured to control supply of electric power to at least one of the communication processor and the contoller in accordance with the power state determined by the contoller.

First claim

What is claimed is:

1. A device having a plurality of power states, the device comprising:
a communication processing circuit configured to communicate with a communication destination device connected via a cable;
a confirmation-signal receiving circuit configured to receive link pulses as a connection confirmation signal that is transmitted if connected to the communication destination device via the cable;
a controller circuit configured to determine a power state depending on whether the confirmation-signal receiving circuit receives the connection confirmation signal; and
a power circuit configured to control supply of electric power to at least one of the communication processing circuit and the controller circuit in accordance with the power state determined by the controller circuit, wherein
if the confirmation-signal receiving circuit does not receive the connection confirmation signal in a first power state where electric power is supplied to the communication processing circuit and the controller circuit, the controller circuit is configured to determine that a transition is to be made to a fourth power state where electric power is supplied to the communication processing circuit but no electric power is supplied to the controller circuit, and
if the communication processing circuit receives a start-up request signal for starting up the device, via the cable while in the fourth power state, the controller circuit is configured to determine that a transition is to be made to a power state where electric power is supplied to the controller circuit.

2. The device according to claim 1 , wherein
if the confirmation-signal receiving circuit does not receive the connection confirmation signal in a first power state where electric power is supplied to the communication processing circuit and the controller circuit, the controller circuit is configured to determine that a transition is to be made to a second power state where no electric power is supplied to the communication processing circuit and the controller circuit, and
if the confirmation-signal receiving circuit receives the connection confirmation signal in the second power state, the controller circuit is configured to determine that a transition is to be made to the first power state.

3. The device according to claim 2 , wherein
a reception signal line for the cable branches to the confirmation-signal receiving circuit and between an interface for the cable and the communication processing circuit,
the device further comprises a switch configured to switch between a connected state and a disconnected state of the reception signal line to the confirmation-signal receiving circuit, and
the switch is configured to be in the disconnected state while in the first power state, and the switch is configured to be in the connected state while in the second power state.

4. The device according to claim 2 , further comprising a setting-information memory configured to store setting information as to whether a transition is to be made to the second power state, wherein
if the confirmation-signal receiving circuit does not receive the connection confirmation signal, the controller circuit is configured to determine whether a transition is to be made to the second power state in accordance with the setting information acquired from the setting-information memory.

5. The device according to claim 1 , wherein if receiving the connection confirmation signal of equal to or more than a predetermined value in a unit of time, the confirmation-signal receiving circuit is configured to determine that the connection confirmation signal is received.

6. The device according to claim 1 , further comprising a nonvolatile memory storing a flag that is set in response to a transition being made to second power state where no electric power is supplied to the communication processing circuit and the controller circuit, to indicate the second power state, wherein
the controller circuit is configured to clear the flag in response to a transition being made to a third power state where no electric power is supplied to the communication processing circuit, the controller circuit, and the confirmation-signal receiving circuit, and
in a case where the confirmation-signal receiving circuit does not receive the connection confirmation signal, the controller circuit is configured to determine that a transition is to be made to the second power state if the flag is set in the nonvolatile memory, and determine that a transition is to be made to the third power state if the flag is not set in the nonvolatile memory.

7. The device according to claim 1 , wherein
a reception signal line for the cable branches to the confirmation-signal receiving circuit and between an interface for the cable and the communication processing circuit, and
a transmission signal line for the cable branches to the confirmation-signal receiving circuit and between an interface for the cable and the communication processing circuit.

8. The device according to claim 1 , wherein
if the confirmation-signal receiving circuit receives the connection confirmation signal while in the fourth power state, the controller circuit is configured to keep the fourth power state, and
if the confirmation-signal receiving circuit does not receive the connection confirmation signal while in the fourth power state, the controller circuit is configured to determine that a transition is to be made to a third power state where no electric power is supplied to the communication processing circuit, the controller circuit, and the confirmation-signal receiving circuit.

9. The device according to claim 1 , wherein
if the confirmation-signal receiving circuit receives the connection confirmation signal while in the fourth power state, the controller circuit is configured to keep the fourth power state,
if the confirmation-signal receiving circuit does not receive the connection confirmation signal while in the fourth power state, it is determined that a transition is to be made to a fifth power state where no electric power is supplied to the communication processing circuit and the controller circuit, and
if the confirmation-signal receiving circuit receives the connection confirmation signal while in the fifth power state, it is determined that a transition is to be made to the fourth power state.

10. The device according to claim 1 , wherein
if the confirmation-signal receiving circuit does not receive the connection confirmation signal while in the first power state, the controller circuit is configured to determine that a transition is to be made to a second power state where no electric power is supplied to the communication processing circuit and the controller circuit, and
if the confirmation-signal receiving circuit receives the connection confirmation signal while in the second power state, the controller circuit is configured to determine that a transition is to be made to the first power state.

11. The device according to claim 10 , wherein
if the confirmation-signal receiving circuit receives the connection confirmation signal while in the fourth power state, the controller circuit is configured to keep the fourth power state,
if the confirmation-signal receiving circuit does not receive the connection confirmation signal while in the fourth power state, it is determined that a transition is to be made to a fifth power state where no electric power is supplied to the communication processing circuit and the controller circuit, and
if the confirmation-signal receiving circuit receives the connection confirmation signal while in the fifth power state, it is determined that a transition is to

Assignees

• Imata Futa
• Ricoh Co Ltd

Inventors

• Imata Futa

Classifications

• H04N1/00888

  Control thereof · CPC title

• G06F1/3296 Primary

  by lowering the supply or operating voltage · CPC title

• G06F1/3243

  Power saving in microcontroller unit · CPC title

• H04L43/0811

  by checking connectivity · CPC title

• Y02D10/152

  Cross-Sectional Technologies · mapped topic