JPH07334280A - Power-on system - Google Patents

Abstract

PURPOSE:To provide the power-on system for supplying a required voltage to a slave device, moreover reducing the number of lines to be connected for communication and further connecting the slave device even during the operation of a main device. CONSTITUTION:This system is provided with insertion monitoring and indicating parts 9 and 14 for detecting whether a peripheral device 2 is connected or not, data transmitting and receiving parts 13 and 8 for communicating data D showing the required power source voltage of the peripheral device 2 to a main body device 1, power source part 5 for generating voltages A, B and C, selector 6 for selecting any one power source voltage of voltages A, B and C and supplying it to the peripheral device 2, and CPU 3 for controlling the selector 6 so as to select the required power source voltage shown by the data D provided at the data receiving part 8 when the insertion monitoring part 9 detects the connection of the peripheral device 2 or for controlling the selector 6 so as to stop the selecting operation when the insertion monitoring part 9 detects no connection of the peripheral device 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power-on system, and more particularly to a power-on system for supplying a power supply voltage to a slave device connected to a main device.

[0002]

2. Description of the Related Art Conventionally, a power-on system of this type is disclosed in, for example, Japanese Patent Application Laid-Open No. 3-280116. FIG. 3 is a diagram showing the structure of the power-on system. In FIG. 3, 100 is a main device,
The main device 100 has a manual power switch 111 and an automatic power-on device 102. The main device 100 responds to the ON operation of the manual power switch 111 by turning on the ON signal 10
In addition to sending 3 to the power-on device 105, the ON signal 104 is sent to the power-on device 105 in response to the automatic power-on by the automatic power-on device 102.

The power-on device 105 responds to the input of the ON signal 103 from the main device 100 to all the peripheral devices 10.
Power is supplied to 7 to 110. That is, by turning on the manual power switch 111, all the peripheral devices 1
07 to 110 are turned on.

The power-on device 105 is provided with changeover switches 161 to 164. The changeover switches 161 to 164 have the ON signal 1 from the main device 100.
Peripheral device 107 to be supplied with power when inputting 04
It is provided to preset up to 110. That is, the power is supplied only to the peripheral devices 107 to 110 corresponding to the preset ones of the changeover switches 161 to 164 in response to the input of the ON signal 104. In this way, the necessary peripheral device 1
Power is supplied only to 07 to 110 to reduce power consumption.

[0005]

However, in the above-described conventional power-on system, the power consumption is saved in the sense that the power supply to the peripheral devices 107 to 110 that do not require power supply is cut off. However, since the peripheral devices 107 to 110 that need power supply are supplied with the same voltage as the main device 100, the following problems occur.

That is, the main unit 100 is used at a high voltage (for example, about 5V) in order to speed up the process.
On the other hand, some of the peripheral devices 107 to 110 operate at a lower voltage (for example, 2 to 3 V) than the main device 100. In the conventional power-on system described above, the main device 10 is used even for peripheral devices operating at such a low voltage.
Since the same voltage as 0 is uniformly supplied, it is not possible to effectively reduce the power consumption.

On the other hand, the peripheral device requests the main device by communication for the power supply of the voltage required for the peripheral device,
It is possible to supply the required voltage to the peripheral device from the main device that received the request, but in this case, the main device and the peripheral device need to communicate with each other. The number of connecting lines for the use increases, and the device becomes complicated.

In general, connecting a peripheral device while the main device such as a personal computer is in operation causes a problem. Therefore, the peripheral device is connected after the main device is turned off. . For this reason, end users are prohibited from connecting peripheral devices with the main device powered on. However, when using a main device such as a personal computer, various peripheral devices are connected. Then, the connection and disconnection of the peripheral device may be performed during the operation of the main device. In such cases,
As described above, if the peripheral device connection or disconnection action is prohibited while the main device is operating, it is inconvenient and the end user's needs cannot be met.

The present invention has been made in view of the above problems. It is possible to supply a required voltage to a slave device, reduce the number of connection lines for communication, and further, to operate the main device. It is an object of the present invention to provide a power-on system capable of connecting a slave device even inside.

[0010]

In order to achieve the above object, in a power-on system of the present invention for supplying power of a main device to a slave device connected to the main device, the power-on system is provided in the main device, Connection detection means for detecting the presence or absence of connection of the device, communication means for communicating data indicating the required power supply voltage of the slave device to the main device, provided in the main device,
A power supply unit capable of generating various power supply voltages, and a selection unit which is provided in the main device, selects any power supply voltage from various power supply voltages generated by the power supply unit, and supplies the selected power supply voltage to the slave device. When the connection means detects the connection of the slave device, the selection means is controlled to select the required power supply voltage indicated by the data obtained by the communication means, and A central control means is provided for controlling the selecting means so as to stop the selecting operation when the connecting means detects non-connection of the slave device.

Further, in the power-on system according to the second aspect of the invention, the connection detecting means is provided in the main unit, and the insertion monitoring unit that holds the H level when the slave unit is not connected to the main unit and the slave unit are provided. It is provided with an insertion instruction unit that changes the level of the insertion monitoring unit to the ground level when the slave device is connected.

Further, in the power-on system according to the third aspect, the communication means is provided in the slave device, and when the selecting means selects the lowest voltage among various power supply voltages of the power means, A data transmission unit that transmits data indicating a power supply voltage required by this slave device to the main device side by an asynchronous communication method, and a data reception unit that is provided in the main device and receives data from the data transmission unit And a section.

Further, in the power-on system according to the present invention, the central control means selects the lowest voltage among various power supply voltages of the power supply means when the connection means detects the connection of the slave device. After controlling the selecting means to monitor the presence or absence of data in the data receiving unit,
When it is determined that there is no data in the data receiving section after a predetermined time has passed, the operation of the selecting means is stopped, and when it is determined that there is data in the data receiving section within the predetermined time, the data indicates The selection means is controlled so as to select the required power supply voltage.

[0014]

According to the above power-on system, when the connection means detects the connection of the slave device, the central control means of the main device controls the selection means so as to select the required power supply voltage indicated by the data obtained by the communication means. Therefore, only the required power supply voltage is supplied to the slave device through the selecting means. Further, when the connecting means detects the non-connection of the slave device, the central control means stops the selecting operation of the selecting means.

According to another aspect of the power-on system of the present invention, when the slave device is not connected, the insertion monitor holds the H level, and when the slave device is connected, the level changes to the ground level. Detects whether the device is connected or not.

According to another aspect of the power-on system of the present invention, when the selecting means selects the lowest voltage among the various power-supply voltages of the power-supply means, the data transmitting section indicates data indicating the required power-supply voltage of the slave device. Is transmitted by an asynchronous communication method,
The data receiving unit receives this data.

Further, according to the power-on system of the fourth aspect, when the connection means detects the connection of the slave device, the minimum voltage is supplied to the slave device, and thereafter, the data receiving unit receives the data within a predetermined time. If the message is not received, the operation of the selection means is stopped, and it is determined as a malfunction. Further, when the data receiving unit receives the data within the predetermined time, the required power supply voltage indicated by the data is supplied to the slave device via the selecting means.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the power-on system of this embodiment. In FIG. 1, a main body device 1 as a main device and a peripheral device 2 as a slave device are a connector 2
It is possible to connect via 0. The main body device 1 includes a CPU 3 as a central control unit, a memory 4, a power supply unit 5 as a power supply unit having a selector 6 as a selection unit, a reset clock generation unit 7, and a data reception unit as a communication unit. 8, an insertion monitoring unit 9 as a connection detecting unit, an interrupt control unit 10, and other electronic circuits (not shown).

The CPU 3 executes various processing operations by the control program in the memory 4. Specifically, the interrupt control unit 1
When receiving the interrupt signal I1 from 0, the control signal C1 is output to the selector 6. When receiving the interrupt signal I2, the built-in timer is started and the presence or absence of the data D in the data receiving unit 8 is monitored. And after the timer starts,
When it is determined that there is no data D in the data receiving unit 8 even after the lapse of a predetermined time, the control signal C2 is output to the selector 6. On the contrary, when it is determined that the data D is present in the data receiving unit 8 within a predetermined time after the timer is started, the data D is read and the control signal C3 corresponding to the content is output to the selector 6.

The power supply unit 5 has a high power supply unit 51 for supplying a voltage A corresponding to the power supply voltage of the main body apparatus 1, an intermediate power supply unit 52 for supplying a voltage B lower than the voltage A, and a voltage higher than the voltage B. And a low power supply unit 53 that supplies a low voltage C.

When the control signal C1 from the CPU 3 is input, the selector 6 operates the low power supply section 53, and when the control signal C3 is input, the voltage indicated by the control signal C3 from the power supply sections 51 to 53 is input. Power supply unit 51 for supplying
(-53) is operated to output these outputs to the power receiving unit 11 of the peripheral device 2. The selector 6 operates the power supply unit 5 when receiving the control signal C2.
Stop 1 (~ 53).

Further, the selector 6 monitors the fluctuation of the voltage of the operated power supply section 51 (to 53). For example, when the low power supply unit 53 is operating, it is determined whether the voltage of the low power supply unit 53 is the voltage C, and when the voltage C is reached, the reset clock generation unit 7 is notified. , And outputs a control signal C4.

When the reset clock generator 7 receives the control signal C4 from the selector 6, the reset clock generator 7 sends a control signal C5 for outputting the interrupt signal I2 to the interrupt controller 10 and resets the reset signal after a lapse of a predetermined time. R is output to the reset clock receiving unit 12 of the peripheral device 2. It should be noted that the above-mentioned predetermined time is set to the time until the entire device stabilizes after the peripheral device 2 receives the power supply voltage from the selector 6.

The data receiving section 8 is for receiving the data D from the data transmitting section 13 of the peripheral device 2. When the peripheral device 2 is not connected, the insertion monitoring unit 9 sets H
The level is held and the GND from the insertion instruction unit 14
When the signal G is received, it becomes the ground level and outputs the insertion signal I to the interrupt control unit 10. Interrupt control unit 10
Outputs an interrupt signal I1 to the CPU3 when the insertion signal I is input from the insertion monitoring unit 9, and outputs an interrupt signal I2 to the CPU3 when the control signal C5 is input from the reset clock generating unit 7. There is.

On the other hand, the peripheral device 2 includes a power receiving unit 11 and
A reset clock receiver 12, a data transmitter 13,
The insertion instruction unit 14 and other electronic circuits (not shown) are provided. The power receiver 11 receives the voltage from the selector 6 and applies the voltage to the entire peripheral device 2.

The reset clock receiving section 12 has a function of operating the data transmitting section 13 when receiving the reset signal R from the reset clock generating section 7 of the main body apparatus 1. The data transmitting section 13 is It has a function of transmitting the data D indicating the power supply voltage required by its own peripheral device 2 to the data receiving unit 8.

Specifically, the data transmitting unit 13 and the data receiving unit 8 are connected by one line, and an asynchronous communication system is adopted. That is, the data D having a header and an end before and after the power supply voltage data is transmitted from the data transmitting unit 13 to the data receiving unit 8 in one direction.

When the peripheral device 2 is connected to the main body device 1 via the connector 20, the insertion instructing unit 14 outputs the GND signal G at the ground level to the insertion monitoring unit 9.

Next, the operation of this embodiment will be described.
First, the case where the main body device 1 is already turned on and is operating will be described based on the operation flowchart of FIG. In this case, the main body device 1 has the high power supply unit 51.
It operates by directly receiving the voltage A from. In this state, when the peripheral device 2 requiring the power supply voltage B is connected to the main body device 1 via the connector 20, the GND signal G from the insertion instruction unit 14 of the peripheral device 2 is monitored for insertion of the main body device 1. Part 9
And the insertion signal I from the insertion monitoring unit 9 is input to the interrupt control unit 10 (YES in step S1 of FIG. 2, step S2).

Then, the interrupt control unit 10 inputs the interrupt signal I1 to the CPU 3, and the CPU 3 outputs the control signal C1 to the selector 6. As a result, the selector 6 operates the low power supply unit 53, so that the power supply voltage of the voltage C is output to the power supply receiving unit 11 of the peripheral device 2 via the connector 20, and the power supply voltage C is supplied to the peripheral device 2. Then, the operation of the reset clock receiving unit 12, the data transmitting unit 13 and the like becomes possible (step S3 in FIG. 2).

Almost in parallel with this operation, the selector 6 outputs the control signal C4 to the reset clock generator 7, and the control signal C5 and the reset signal R are reset from the reset clock generator 7 to the interrupt controller 10 and reset. Clock receiver 12
And are output (step S4 in FIG. 2). In the interrupt control unit 10 which has received the control signal C5, the interrupt signal I2
Is output to the CPU 3, a timer built in the CPU 3 is started, and the data D in the data receiving unit 8 is output by the CPU 3.
Whether or not is monitored (steps S4 and S5 in FIG. 2).

On the other hand, when the reset signal R is input to the reset clock receiver 12 of the peripheral device 2, the data transmitter 13 is operated and the data D indicating the required voltage B is asynchronously received from the data transmitter 13. It is output to the unit 8. After the above timer starts, the data D
When the data is received by the data receiving unit 8, the CPU 3 causes
The content of the data D is read, and the control signal C3 indicating the voltage B is output from the CPU 3 to the selector 6 (step S in FIG. 2).
YES of 5).

As a result, the selector 6 operates in the low power supply section 53.
Since the middle power supply unit 52 is operated after stopping the operation of No. 1, the power source voltage of the voltage B is output from the selector 6 to the power receiving unit 11 of the peripheral device 2, and the power receiving unit 11 keeps the voltage B around. It is supplied to the entire device 2 (step S in FIG. 2).
6). Therefore, even when the peripheral device 2 requires the power supply voltage of the voltage A or the voltage C, the power supply voltage is supplied by the same operation as described above.

In this way, the peripheral device 2 can be connected to receive power supply even while the main body device 1 is operating,
Moreover, since only the necessary voltage is supplied to the peripheral device 2,
It is convenient for the end user, and the power consumption of the power supply unit 5 of the main body device 1 can be reduced.

Further, the main body device 1 may malfunction even though the peripheral device 2 is not connected. For example, when the insertion monitoring unit 9 malfunctions, the insertion signal I is output to the interrupt control unit 10, and the reset clock generation unit 7 resets the reset signal R via the operation of the CPU 3 and the selector 6.
Is output, but in this case, since the data D is not input to the data receiving unit 8, after the timer is started,
The CPU 3 cannot read the data D in the data receiving unit 8 even after a predetermined time has elapsed (Y in step S1 in FIG. 2).
ES, S2-S5). As a result, the control signal C2 becomes
3 is output to the selector 6, and the power supply units 51 to 53 that are currently operating are stopped, so that useless power consumption does not occur (NO in step S5 and S7 in FIG. 2).

Further, since the data D indicating the required voltage of the peripheral device 2 is output from the data transmitting unit 13 to the data receiving unit 8 through one line by the asynchronous communication method, the communication is remarkably compared with the synchronous communication. The number of lines can be reduced,
Therefore, the device can be simplified.

When the peripheral device 2 is disconnected from the main body device 1 while the main body device 1 is operating, the input of the GND signal G from the insertion instructing section 14 to the insertion monitoring section 9 is cut off, and the insertion monitoring section 9 is disconnected. Changes to the H level, so that the insertion signal I is not output to the interrupt control unit 10, and as a result, the output of the control signal C3 from the CPU 3 is cut off, and the power supply units 51 to 5 are connected.
3 stops (NO in step S1 of FIG. 2, S
7).

Finally, the operation when the peripheral device 2 which requires the power supply voltage B is connected to the main body device 1 which is not powered on will be described. First, when the user turns on the power of the main body device 1, the main body device 1 is turned on by the high power supply unit 51.
It receives the voltage A directly from it and operates. In this state, since the GND signal G from the insertion instruction unit 14 of the peripheral device 2 is input to the insertion monitoring unit 9 of the main body device 1, the insertion monitoring unit 9
From the interrupt control unit 10, the interrupt signal I1 is input from the interrupt control unit 10 to the CPU 3, and C
The control signal C1 is output from the PU 3 to the selector 6.

As a result, the low power supply section 53 is operated, and the power supply voltage of the voltage C becomes the power supply receiving section 11 of the peripheral device 2.
In addition, the control signal C4 from the selector 6 causes the control signal C5 and the reset signal R to be output from the reset clock generator 7 to the interrupt controller 10 and the reset clock receiver 12, respectively. As a result, the reset signal R
The data D indicating the required voltage B is asynchronously output to the data receiving unit 8 by the input to the reset clock receiving unit 12.

When the data receiving section 8 receives the data D, the contents of the data D are read by the CPU 3, and the control signal C3 indicating the voltage B is sent from the CPU 3 to the selector 6
Is output to. As a result, the middle power supply unit 52 is operated by the selector 6, the power supply voltage of the voltage B is output to the power reception unit 11 of the peripheral device 2, and the voltage B is supplied to the entire peripheral device 2. Other operations are the same as the operations when the peripheral device 2 is connected while the main body device 1 is operating.

[0041]

As described above, according to the power-on system of the present invention, when the slave device is connected to the master device, only the power supply voltage necessary for the slave device is supplied, so that the power consumption of the power supply is reduced. Can be realized. Further, since the slave device can be connected regardless of the operation of the master device, it is convenient for the end user. Furthermore, since the data indicating the required power supply voltage of the slave device is transmitted by the asynchronous communication method, the number of communication lines can be significantly reduced as compared with the synchronous communication method.

[Brief description of drawings]

FIG. 1 is a block diagram showing a power-on system according to an embodiment of the present invention.

FIG. 2 is an operation flowchart of the present embodiment.

FIG. 3 is a block diagram showing a power-on system according to a conventional example.

[Explanation of symbols]

 1 Main Unit 2 Peripheral Device 3 CPU 5 Power Supply Unit 6 Selector 8 Data Receiver 9 Insertion Monitor 14 Insertion Instructor 13 Data Transmitter

Claims (4)

[Claims] 1. A power-on system for turning on the power supply of a main device to a slave device connected to the main device, the connection detecting means being provided in the main device, for detecting whether or not the slave device is connected, and the slave device. Communication means for communicating data indicating required power supply voltage of the device to the main device, power supply device provided in the main device for generating various power supply voltages, and provided in the main device, generated by the power supply device When any one of various power supply voltages is selected and is supplied to the slave device, and selecting means is provided in the master device, and the connection means detects the connection of the slave device, the communication is performed. The selection means is controlled so as to select the required power supply voltage indicated by the data obtained by the means, and when the connection means detects the non-connection of the slave device, the selection is stopped. Means Power-system, comprising a central control means for Gosuru, the. 2. The insertion detecting unit, which is provided in the main device and holds an H level when the slave device is not connected, and the insertion monitor, which is provided in the slave device, when the slave device is connected. The power-on system according to claim 1, further comprising an insertion instructing unit that changes the level of the unit to the ground level. 3. The communication means is provided in the slave device, and indicates the power supply voltage required by the slave device when the selecting means selects the lowest voltage among various power supply voltages of the power supply means. The data transmitting unit for transmitting data to the main device side by an asynchronous communication method, and the data receiving unit provided in the main device for receiving data from the data transmitting unit. The power-on system described. 4. The central control means controls the selection means so as to select the lowest voltage among various power supply voltages of the power supply means when the connection means detects the connection of the slave device. The presence or absence of data in the data receiving unit is monitored, and when it is determined that there is no data in the data receiving unit after a lapse of a predetermined time, the operation of the selecting unit is stopped, and the data receiving unit is also operated within the predetermined time. 4. The power-on system according to claim 3, wherein when it is determined that there is data, the selecting means is controlled to select the required power supply voltage indicated by the data.