JPH0358345A - Power source control system for disk device - Google Patents

Abstract

PURPOSE:To obtain an electronic device without requiring a battery circuit by providing a power source circuit dedicated for a disk control circuit and a disk device, and controlling the output of the circuit by monitoring an input power source state. CONSTITUTION:The disconnection information of a power source switch 107 is transmitted to the power source circuit 111, and a timer circuit 112 in the power source circuit 111 is started up, and simultaneously, the disconnection information is transmitted to the disk control circuit 104. Meanwhile, when power failure, hit, or momentary stoppage occur, a power source monitoring circuit 113 in the power source circuit 11 is activated, and it is transmitted to the disk control circuit 104 via a voltage reduction state output signal line 109. the control circuit 104 receives it, and is operated so as to evade unauthorized access to a disk device 105 due to a false control signal whose logic in indefinite generated when the voltage drops by closing a control signal line which makes access the disk device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power supply control method for an electronic device having a disk device.

[Conventional technology]

Conventionally, in this type of power control system, as shown in FIG.
02 is installed, and when the input power is cut off, it switches to the backup battery circuit 211, notifies this to the disk control circuit 204, and guarantees the access to the disk device 205 that was being made at that time. ,
The configuration was such that unauthorized access to the disk device 205 that occurs when the power is turned off is avoided.

[Problem to be solved by the invention]

However, in the conventional power supply control system described above, since the power supply circuit includes a battery circuit, the battery must be replaced periodically, which is very uneconomical in terms of maintenance.

[Means to solve the problem]

A power supply control system for a disk device according to the present invention includes a disk control circuit and a dedicated power supply circuit for the disk device, in addition to a power supply circuit for a general logic circuit, in an electronic device having a disk device. means for notifying the disconnection state to the disk control circuit when an input power switch of a power supply circuit for a logic circuit is disconnected and disconnecting its own input power supply after a predetermined time has elapsed; and means for notifying the disk control circuit of this state when the following conditions occur.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

Referring to FIG. 1 showing an embodiment of the present invention, 101 is an electronic device, 102 is a general logic circuit power supply circuit, 103 is a general logic circuit, 104 is a disk control circuit, 105 is a disk device, and 106 is a temporary side. A power supply line, 107 is a power switch for the power supply circuit 102, 108 is a secondary power supply line for the general logic circuit, 109 is a secondary power supply line for the disk control circuit and disk device, 110 is a voltage drop state output signal line, 1
11 is a disk control circuit and a disk device power supply circuit;
112 is a timer circuit, 113 is a power supply voltage monitoring circuit, 1
14 is a power switch for the power supply circuit 111, 115 is a power switch state input signal line, 116 is a power switch state output signal line, and 117 is a power switch control signal line.

Here, the electronic device 10 is manually turned off using the power switch 107.
1, the disconnection information of the power switch lO7 is transmitted to the power supply circuit 111 via the power switch state input signal line 115, and the timer circuit 112 in the power supply circuit 111 receives this information and starts a timer. At the same time, this disconnection information is sent to the power switch status output signal line 116.
The data is transmitted to the disk control circuit 104 via. If the disk control circuit 104 is accessing the disk device 105 when it receives this, it determines whether to terminate the access to the specific address midway according to the instruction from the general logic circuit 103. , or after completion, it operates to retract the head to the evacuation area. The timer circuit 112 has a predetermined timer value sufficient to guarantee the above operation of the disk control circuit 104, and automatically turns off the power switch 114 via the power switch control signal line 117 when this set value is reached. Give instructions to disconnect.

In addition, when a two-moment power outage or a momentary power outage occurs, the power supply voltage monitoring circuit 113 in the power supply circuit 111 is activated, and the power supply voltage monitoring circuit 113 in the power supply circuit 111 is activated, and the voltage drop state output signal line 109 is output to the disk control circuit 109.
Communicate this to. In response to this, the disk control circuit 104 closes the control signal line for accessing the disk device 105, thereby avoiding unauthorized access to the disk device 105 due to pseudo control signals with uncertain logic that occur when the voltage drops. Operate.

〔Effect of the invention〕

As explained above, according to the present invention, a dedicated power supply circuit for a disk control circuit and a disk device is provided, and the input power status is monitored and the output is controlled, thereby easily and economically eliminating the need for a battery circuit. An electronic device can be constructed.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional example. 101, 201...Electronic device, 102...
...Power supply circuit, 103,203...General logic circuit, 104,204...Disk control circuit, 1
05,205...Disk device, 106,206
...Primary side power line, 107...Power switch, 108,208...Secondary side power line, 109
, 209... Secondary power supply line, 110, 210...
...Voltage drop state output signal line, 111...
・Power supply circuit, 112... Timer circuit, 113
...Power supply voltage monitoring circuit, 114...Power switch, 115...Power switch state input signal line, 116...Power switch state output signal line, 117 ...Power switch control signal line, 202
...Power supply circuit, 207 ...Power switch, 211 ...Battery circuit.

Claims (1)

[Claims] In addition to a power supply circuit for the general logic circuit, a disk control circuit and a dedicated power supply circuit for the disk drive are provided in an electronic device having a disk drive, and this power supply circuit is disconnected when the input power switch of the power supply circuit of the general logic circuit is turned off. means for notifying the disk control circuit of the disconnection state when the input power supply voltage is lower than a predetermined value and for disconnecting its own input power supply after a predetermined time has elapsed; 1. A power control method for a disk device, comprising: means for notifying the user.