JP2005250943A - External connection equipment and processor capable of being supplied with power via interface means - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent troubles caused by a decrease in the battery remaining capacity of a processor which has been caused when connected to external connection equipment to which power is supplied via an interface. <P>SOLUTION: When a host 1 is driven by a battery and connected to the external connection equipment 2 driven via the interface such as a USB, the host 1 displays a message showing that its time for driving is shortened or the like to attract a user's attention. When a power adapter is connected to the external connection equipment 2, the host 1 is notified that external power driving is switched to, and after a state that data transfer is not performed is confirmed, the external connection equipment is set in an inactive state, the external connection equipment is switched to the external power driving from power supply from the interface, the external connection equipment is reset, and an initial sequence is executed. Also, a test button is provided in the external connection equipment to thereby confirm power supply situations of the host 1. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an external connection device that is connected to a processing device such as a personal computer or a PDA and can supply power via an interface such as USB / IEEE1394, and a processing device to which the external connection device is connected.

Externally connected devices such as MO devices and hard disk devices that can supply power via an interface such as USB / IEEE1394 are widely used. These interfaces have a power supply bus, and drive power can be supplied from a processing device such as a personal computer to the external connection device via this bus. When the external connection device is connected to the processing device and driving power is supplied from the processing device via the interface, the power consumption of the processing device increases.
Therefore, in the drive device that supplies drive power from the computer via the interface, the drive device detects the type of the power source of the computer and suppresses the power consumption of the drive device when driven by a power source with low capability Has been proposed (see, for example, Patent Document 1).
JP 2002-312081 A

In the case of a processing device such as a notebook personal computer or a PDA driven by a battery, if the externally connected device is connected while the battery is driven, the power consumption of the battery increases and the battery is consumed quickly.
For this reason, there is a case where the remaining capacity of the battery is remarkably lowered unexpectedly and the processing apparatus stops. In particular, if a large amount of data is transferred when the remaining capacity of the battery is small, the battery of the processing device may be consumed during the data transfer, and the processing device may be stopped in many cases, thereby reducing reliability.
The user is not necessarily aware that power is being supplied from the battery of the processing device to the externally connected device, and does not always check the remaining capacity of the battery. Therefore, it is difficult to know how much the battery will be consumed, so the possibility of the above troubles is high.
Conventionally, there has been no method for notifying the user that an external connection device that supplies driving power via the interface is connected to the processing device. For this reason, the above trouble often occurs.

On the other hand, the externally connected device is supplied from a mode in which the externally connected device is operated with driving power from the interface (hereinafter referred to as a bus power mode) and a power adapter that performs AC-DC conversion. Some of them can be used in combination with a mode in which an externally connected device is operated with driving power (hereinafter referred to as a self power mode).
However, switching from the bus power mode to the self power mode or switching from the self power mode to the bus power mode while driving the externally connected device, for example, in the case of a USB bus, requires a reset process and is easily performed. I couldn't.
That is, in order to switch from the bus power mode to the self power mode, it is necessary to disconnect and reconnect the USB cable and to electrically disconnect the USB interface. If it is performed while the externally connected device is being driven, data being transferred or data in the write cache may be lost or data may be damaged, and switching cannot be performed easily.
For this reason, when the remaining capacity of the battery decreases during operation in the bus power mode, even if the power adapter is connected to an external device, the switch from the bus power mode to the self power mode will not be performed. The processing apparatus may stop due to a decrease in the remaining capacity.

Normally, a notebook computer or the like that is driven by a battery has a function of displaying the remaining battery capacity. However, when an external device that operates in the bus power mode is connected, the current remaining battery capacity is used. Whether or not the normal operation can be continued cannot be displayed, and the remaining battery capacity may be rapidly reduced due to the connection of the externally connected device, and the normal operation may not be continued.
The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent a trouble caused by a decrease in remaining battery capacity that occurs when an externally connected device to which power is supplied via an interface is connected. More specifically, in the externally connected device, switching from the bus power mode to the self-power mode can be easily performed, and when the externally connected device is connected to the processing device, the interface is connected. By displaying that the externally connected equipment to be powered is connected, or by displaying whether or not normal operation is possible with the current remaining battery capacity, the processing device can be stopped due to a decrease in remaining battery capacity. It is to prevent it.

In the present invention, the above problem is solved as follows.
(1) In an externally connected device connected to a processing apparatus and driven by an external power source supplied via a power supply terminal or a power supply supplied from the processing apparatus via an interface means, via the interface means When power is supplied, it is detected that an external power source is connected to the power supply terminal, and when it is detected that an external power source is connected, the processing device is notified that switching to external power source driving has been performed. Then, after confirming the state in which data transfer is not performed, the externally connected device is set to a dormant state, and the externally connected device is switched from being driven by a power source via the interface means to being driven by an external power source. Reset and initialize the connected device.
(2) In an externally connected device connected to a processing device and driven by a power source supplied from the processing device via an interface unit, the device is connected to the externally connected device by a power source supplied via the interface unit. A test button is provided to test whether it can be driven.
When the external connection device is not in operation, the external connection device is connected to the processing device via the interface means, and when the test button is pressed, a current greater than a predetermined value is drawn from the processing device. Whether or not the device can be driven by power supply via the interface means is displayed based on the determination result.
(3) In a processing apparatus connected to an externally connected device capable of supplying power via an interface unit, the processing unit determines whether the battery is driven or an external power source is used, and the interface unit is Determining whether or not an externally connected device that supplies power is connected, and in a battery-powered state, and determining that an externally connected device that is supplied with power via the interface means is connected, Displays a warning that the power may be low.

In the present invention, the following effects can be obtained.
(1) When an external power supply is connected, it is possible to switch from driving by the power supply via the interface means to external power supply driving. Therefore, when the battery of the processing device is exhausted, switching to the external power supply is easy. Is possible. Further, by displaying that the driving from the power source via the interface means is switched to the external power source driving, the user can easily confirm the power supply status.
(2) By enabling the test button to check the power status of the processing device before the operation of the externally connected device, the battery of the processing device is depleted while the externally connected device is connected, and the processing device is stopped. Therefore, it is possible to prevent the trouble such as the device read / write, and to improve the operation security of the device Read / Write. Further, in a situation where it is not possible to operate with the battery of the processing apparatus, it is possible to clarify whether or not the connection is operable by disconnecting the externally connected device.
(3) When the processing device is operating on a battery, the external power supply is displayed in consideration of the remaining amount of the battery by displaying that the externally connected device to which power is supplied via the interface means is connected. Can be used to prevent problems such as the processing device being stopped due to battery exhaustion while using externally connected devices, and improving the reliability of data, etc. Become.

Examples of the present invention will be described below. In the following description, the processing device is a notebook personal computer and the externally connected device is an MO device. However, if the device is battery-driven, it can be similarly applied to other processing devices. The external connection device may also be a device other than the MO device.
FIG. 1 is a diagram showing a device configuration of an embodiment of the present invention.
In the figure, 1 is a notebook personal computer (hereinafter referred to as host 1) that can be driven by a battery, and 2 is an MO device. The host 1 and the MO device are connected via an interface having a power supply bus such as USB or IEEE1394. In the following, a case will be described in which the host and the MO device are connected via a USB interface (including both USB 1.1 and USB 2.0).
The host 1 includes the USB interface circuit 1a, a file system driver, a driver for driving the MO device, various drivers 1b such as a driver for driving a USB controller, and the like, and an application program 1c.
The MO device 2 includes the USB interface circuit 2a, a computer (MPU) 2b connected to the interface circuit via a bus, a ROM, a RAM, etc., and a storage unit 2c for storing programs and data, a cache The memory 2d, the MO drive device 2e, and the like are included.
The interface circuits 1 a and 2 a have a USB connector and are connected via a USB cable 3. Note that the MO device 2 of this embodiment includes an external power supply terminal for supplying power from the outside via the power adapter 4, and supplies driving power via the USB cable 3 as shown in FIG. It is assumed that a bus power (BUS power) mode and a self power (self power) mode for supplying driving power via the power adapter can be used in combination.

First, when an MO device operating in the bus power mode is connected to the host (or HUB) according to the first embodiment of the present invention, this is displayed on the host display device to call attention. The embodiment described above will be described.
FIG. 3 is a flowchart showing an outline of processing when an MO device operating in the bus power mode is connected to the host.
When the MO device is connected by USB connection when the battery is not driven by the host, the host checks whether or not a medium is set in the MO device (step S1 → S4). Step S5) If the medium is set, the medium is accessible (steps S6 and S7).
Further, when the MO device is connected by USB connection during battery driving, it is determined whether the MO device is in the bus power mode or the self power mode (steps S2 and S3). If it is not the bus power mode, it is checked whether or not a medium is set in the MO device. If there is no medium, the mode shifts to the idle mode (step S5). If the medium is set, the medium can be accessed. (Steps S6 and S7).
Also, in the bus power mode, there is a possibility that the drive time of the host will be shortened because the device connected to USB is driven by BUS power in the window of the display screen. Please use the external power supply "message is displayed (step S8), and the process goes to step S4.

FIG. 4 is a flowchart showing the USB protocol processing of the host 1 when the USB connector is inserted in FIG. 3, and FIG. 5 is a diagram for explaining the host driver configuration and the mechanism for displaying the above.
In FIG. 4, when the USB connector of the MO device operating in the bus power mode and the USB connector of the host are connected by a USB cable, the USB protocol of the host issues a command for acquiring a descriptor to the MO device. The address (ID) of the MO device is set (steps S1 and S2). Next, the USB interface is reset, a descriptor is acquired from the MO device, and a report indicating whether the power mode is the bus power mode or the self power mode is received from the MO device (steps S3 and S4).
The host sets configuration information based on the descriptor from the MO device, and in the bus power mode, supplies a current of, for example, 500 mA to the MO device via the USB cable power supply bus ( Step S5). If the bus power mode is not used, the self power mode is set and the power feeding is not performed.
In addition, the host application is notified via the Plug in / out driver that the bus power mode has been entered (step S7), and a transition is made to the normal data transfer mode (step S6). Upon receiving the notification, the application displays a message indicating that a device in the bus power mode is connected on the display screen of the host.

As shown in FIG. 5, the host to which the MO device is connected includes a controller that controls the MO device 2, a driver for the controller, a command driver, a plug in / out driver, a media ID driver, an MO driver, a file system driver, and the like. The driver is provided with an application program at the upper level.
When it is notified from the USB protocol that the bus power mode has been entered as shown in FIG. 4, the Plug in / out driver recognizes that the bus power mode has been entered, as shown in FIG. Notify the application program to that effect. As a result, the application program displays, for example, a message as shown in FIG. 5 on the display screen as described above. This display is displayed in the same manner as the message displayed on the screen of the personal computer when the USB connection is made, for example.
As described above, by displaying on the display screen that the bus power mode has been entered, it is possible to alert the user, and the user uses an external power source in consideration of the remaining battery level, etc. As described above, it is possible to prevent the trouble that the personal computer is stopped due to the consumption of the battery while using the MO device.

By the way, as described above, in the prior art, switching from the bus power mode to the self power mode requires the USB cable to be disconnected and then connected again, and the external power supply can be connected with the USB cable connected. Even so, it was not possible to switch to the self-power mode.
In the present invention, it is possible to switch from the bus power mode to the self-power mode without reconnecting the USB cable by connecting an external power supply. Hereinafter, the second embodiment of the present invention will be described. An example of processing for switching from the bus power mode to the self power mode, which is an example, will be described.

FIG. 6 is a flowchart showing a process of switching from the bus power mode to the self power mode when an external power supply is connected.
When a DC power supply is connected to the MO device driven in the bus power mode, the MO device notifies the host that the DC power supply is connected, and generates a status indicating that the external power supply is connected (step S1). ~ S4). Note that the host may detect that a DC power source is connected to the MO apparatus by polling.
Thereby, the host knows that the DC power source is connected to the MO apparatus, and displays that the DC power source is connected to the window of the display screen and that the USB connector is unplugged (steps T1 to T2). ). As described in the first embodiment, this processing can be performed by notifying the host application from the USB protocol via the Plug in / out driver.
On the other hand, in the MO device, an interrupt for notifying that the DC power source is connected is given to the control program (firmware) of the MO device.
The firmware of the MO device confirms that there is no data transfer on the interface and that there is no unwritten data in the cache, and in this state, sets the device to sleep mode (sleep mode) ( Steps S5 and S6). The MO device is suspended.

Next, the MO device is switched from the bus power mode to the self power mode under the control of the firmware (step S7). Further, the interface is temporarily disconnected, and a reset of the USB interface of the MO device is issued from the host (step T3).
As a result, the USB interface of the MO device is inserted and removed, and an initial sequence is executed (step S8). That is, the process shown in FIG. 4 is performed.
The MO device is switched to the DC power supply drive, and the fact that the bus power mode is switched to the self power mode is displayed by blinking the LEDs (steps S9 and S10). Note that the LED may be an existing LED provided in the MO device.
As described above, when the DC power source is connected to the MO device, the bus power mode can be switched to the self power mode, so that when the host battery is exhausted, the switching to the DC power source can be easily performed. It becomes possible.
In addition, the display screen window indicates that the DC power supply is connected, the USB connector is unplugged, and the fact that the bus power mode is switched to the self power mode is displayed by blinking LEDs. As a result, the user can easily confirm the power supply status, such as whether the MO device is operating in the bus power mode or the self power mode.
The first embodiment and the second embodiment are used together to display on the display screen that the MO device driven in the bus power mode is connected, and as described above, the MO device When a DC power source is connected to the power source, the bus power mode may be switched to the self power mode.

Next, a description will be given of a third embodiment of the present invention in which it is tested whether normal operation can be continued with the current remaining battery capacity when an MO device operating in the bus power mode is connected. .
FIG. 7 is a diagram illustrating the configuration of the MO apparatus according to the present embodiment.
The host 1 and the MO device 2 are connected via a USB cable 3, and the USB cable 3 includes a power supply bus 31 and a data bus 32, and these buses are connected to the USB controller 21 of the MO device 2.
The MO device 2 includes a power adapter terminal 22 to which DC power is supplied. In conjunction with the insertion / removal of the power adapter, the auxiliary contact 22a of the receiving DC jack is turned on / off, and the switch SW1 is controlled. When DC power is supplied from the power adapter, the switch SW1 is turned off, and the bus power mode is switched to the self power mode.

The MO device 2 includes a test switch SW2 that operates by operating a test button and the like, and a current load circuit 23. When the test switch SW2 is turned on, the current load circuit 23 is connected to the power supply bus 31. The test switch SW2 is connected to the I / O port 25a of the MO controller 25, and the state of the test switch SW2 is given to the MO controller 25. The test switch SW2 can also be controlled by the MO controller 25.
A voltage detector 24 for detecting the voltage of the power supply bus 31 is connected between the test switch SW2 and the current load circuit 23. The voltage VS detected by the voltage detector 24 is This is given to the MO controller 25. The MO controller 25 sets the load current set value IL of the current load circuit 23.
The MO device 2 is provided with an LED 26 for displaying a bus power test result, and the LED 26 is connected to the I / O port 25 b of the MO controller 25.
For example, as shown in FIG. 8, the test button and the LED 26 for displaying the test result are provided on the side surface or the front surface of the MO apparatus.

FIG. 9 is a flowchart showing a process for testing whether normal operation can be continued with the current remaining battery capacity. The confirmation test of this embodiment will be described with reference to FIG.
First, in a state where no medium is inserted in the MO device, the power adapter is connected to the power adapter terminal 22 and the MO device 2 is connected to the host 1 by the USB cable. Then, the test button is pressed to turn on the test switch SW2 to enter the test mode (steps S1 and S2). By connecting the power adapter as described above, the external power is supplied to the USB controller 21, the MO controller 25, the current load circuit 23, and the like, the switch SW1 is turned off, and the power supply bus 31 switches the switch SW2. To the current load circuit 23.
It should be noted that the test mode may be changed by the firmware of the MO apparatus. That is, after connecting the AC adapter, when the MO device 2 and the host 1 are connected by the USB cable 3, the test switch SW1 may be turned on by the MO controller 25 to switch to the test mode.

In the test mode, the MO controller 25 increases the value of the current load IL of the current load circuit 23 with time, and reads the voltage VS detected by the voltage detector 24 at each current value. For example, the current load set value is increased to 0.4 A, 0.5 A, and 0.6 A, and the voltage VS at each current load is read. When the current load of the current load circuit 23 is set as described above, a current corresponding to the current load flows into the current load circuit 23 from the battery of the host 1 through the power supply bus 31.
If the remaining capacity of the battery of the host 1 is sufficient, when the current is drawn as described above, the detection voltage VS by the voltage detector 24 does not decrease so much, but if the remaining capacity of the battery is small, it is shown in FIG. As described above, when the value of the current load exceeds a certain value, the voltage VS rapidly decreases.
The MO controller 25 determines how much current can be drawn from the host battery (step S3 in FIG. 9). For example, if the current can be drawn up to 500mA at 5V (the voltage does not decrease even if the current of 500mA is drawn), it is determined that the remaining battery level is sufficient, and the LED 26 of the MO device is lit in green, and the bus power Is displayed (step S4 in FIG. 9). Thus, it is confirmed that the MO device can be driven by the bus power, and the user releases the test button to end the test (step S5).

On the other hand, if the current cannot be drawn up to 500 mA, it is determined that the remaining battery level is not sufficient, and the LED 26 of the MO device is turned off. Also, the bus power supply is stopped and the connection with the host is disconnected (step S6). Thus, it can be seen that the MO device cannot be driven by the bus power, and the user releases the test button, ends the test, and pulls out the USB cable from the connector (step S7).
As described above, the MO device is provided with a test button, and when the test button is pressed, by determining how much current can be drawn from the host battery via the current supply bus, the MO device can be operated with bus power. Thus, it is possible to prevent a problem that the host battery is consumed and the host stops while the MO device is being driven by bus power.
In addition to the test function described in the third embodiment, the MO device may be provided with a function of switching from bus power to self power described in the second embodiment. The function described in the example may be provided in the host.

It is a figure which shows the apparatus structure of the Example of this invention. It is a figure which shows the example of the MO apparatus which can switch a bus power mode and a self power mode. It is a flowchart which shows the outline | summary of a process when the MO apparatus which operate | moves in a bus power mode is connected to the host. 4 is a flowchart showing host processing when a USB connector is inserted in FIG. 3. It is a figure explaining the mechanism which displays that the MO driver which operate | moves in the driver configuration of a host and a bus power mode was connected. It is a flowchart which shows the switching process from the bus power mode at the time of an external power supply connection to the self power mode. It is a figure which shows the structure of MO apparatus provided with the function which tests whether MO apparatus can continue normal operation with the present battery remaining capacity. It is a figure which shows the example of arrangement | positioning of LED which displays a test button and a test result. It is a flowchart which shows the process for testing whether normal operation | movement can be continued with the present battery remaining capacity. It is a figure explaining the voltage fall when the drawing-in electric current value from a battery increases.

Explanation of symbols

1 Host (notebook computer)
2 MO device 21 USB controller 22 Power adapter terminal 23 Current load circuit 24 Voltage detector 25 MO controller 26 LED
3 USB cable 31 Power supply bus 32 Data bus 4 Power adapter

Claims (3)

A power source connected to the processing device and supplied from the processing device via the interface means, or an external connection device driven by an external power source supplied via the power supply terminal,
The externally connected device, when supplying power via the interface means, detecting means for detecting that an external power supply is connected to the power supply terminal;
Means for notifying that the processing device has been switched to the external power drive when the detection means detects that an external power supply is connected;
After confirming the state where data transfer is not performed, the externally connected device is set to a dormant state, and the externally connected device is switched from driving by the power source through the interface unit to external power source driving means, and
An external connection device capable of supplying power from interface means, comprising means for resetting and initializing the external connection device. An external connection device connected to the processing device and driven by a power source supplied from the processing device via the interface means,
The external connection device is a test button for testing whether the device can be driven by the power supplied via the interface means;
When the externally connected device is not operating, the externally connected device is connected to the processing device via the interface means, and when the test button is pressed, a current greater than a predetermined value can be drawn from the processing device. Determination means for determining whether there is,
An external connection device capable of supplying power from the interface means, comprising: means for displaying whether or not the device can be driven by power supply via the interface means based on the determination result. A processing device connected to an external connection device capable of supplying power via an interface means,
The processing apparatus includes: a first determination unit that determines whether the battery is in a battery-driven state or an external power supply usage state;
Second determination means for determining whether or not an external connection device for supplying power is connected via the interface means;
When the first determination means determines that the battery is driven and the second determination means determines that an externally connected device to which power is supplied via the interface means is connected, A processing apparatus comprising means for displaying a warning that there is a risk of a decrease.

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