Electronic device having power saving function and extension unit

• US 20020115481A1
• Filed: 01/30/2002
• Published: 08/22/2002
• Est. Priority Date: 02/22/2001
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Saito, Keiji
• Granted Patent: US 6,957,082 B2
• Time in Patent Office: Days
• US Class Current: 455/574
• CPC Class Codes: H04B 1/3816 Mechanical arrangements for accommodating identification devices, e.g. cards or chips; with connectors for programming identification devices
• CPC Class Codes: H04M 1/72409 by interfacing with external accessories hands-free H04M1/60
• CPC Class Codes: H04M 1/72412 using two-way short-range wireless interfaces
• CPC Class Codes: H04M 2250/14 including a card reading device
• CPC Class Codes: H04W 52/0274 by switching on or off the equipment or parts thereof
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

When the connector of an electronic card device is mated with the connector of a host device with the main power supply of the host device being turned off, a power supply control unit in the host device starts the supply of power to the card device. When no operating command is received from the host device within a fixed period after the start of reception of power, a central processing unit of the card device determines that the main power supply of the host device is turned off and starts radio communication using a radio communication unit on the basis of operating commands stored in an information storage unit.

Claims

1. An electronic device in which an expansion unit is removably connected, comprising:

a command device configured to give a command to supply power to the expansion unit; and

a power supply control device configured to start the supply of power to the expansion unit when a command is given by the command device in a state where the electronic device is turned off.

2. The electronic device according to claim 1 including a notification device configured to notify the expansion unit of the on/off state of the main power supply in the electronic device.

3. The electronic device according to claim 1 including comprising a receiving device configured to receive from the expansion unit a command to stop the supply of power, and wherein the power supply control unit stops the supply of power to the expansion unit in response to said command from the expansion unit.

4. An electronic device in which an expansion unit is removably connected, comprising:

a detection device configured to detect whether or not the expansion unit is connected to the connection device; and

a power supply control device configured to start the supply of power to the expansion unit when connection of the expansion unit is detected by the detection device in a state where the electronic device is turned off.

5. The electronic device according to claim 4 including a notification device configured to notify the expansion unit of the on/off state of the main power supply in the electronic device.

6. The electronic device according to claim 4 including a receiving device configured to receive from the expansion unit a command to stop the supply of power, and wherein the power supply control unit stops the supply of power to the expansion unit in response to the said command from the expansion unit.

7. An expansion unit powered from an electronic device for increasing the functions of said electronic device comprising:

a detection device configured to detect the presence or absence of power from the electronic device; and

a control device configured to carry out a given processing when no operating command comes from the electronic device within a predetermined period after power from the electronic device has been detected by the detection device.

8. The expansion unit according to claim 7 including a storage device configured to store operating commands to execute the preset processing, and wherein the control device executes the preset processing on the basis of the operating commands stored in the storage device.

9. The expansion unit according to claim 7 including a transmission device configured to transmit a command to stop the supply of power to the expansion unit at the termination of execution of the preset processing by the control device.

10. The expansion unit according to claim 7 including a radio communication device, and wherein the control device executes as the preset processing a process of radio communication with another electronic device using the radio communication device.

11. A power supply control method for an electronic device in which an expansion unit is removably connected, the method comprising:

giving a command to supply power to the expansion unit; and

starting the supply of power to the expansion unit when a command is given in a state where the electronic device is turned off.