JPH0376048A - Disk protecting system in power failure - Google Patents

Abstract

PURPOSE:To prevent such undesirable effect as data destruction or disk damage by continuing the supply of a power by switching to an internal power source when the power failure happened, and disconnecting the supply of power from the internal power source after making a head back to a home position. CONSTITUTION:When power failure is detected, a power failure detecting means 3 controls a switching means 4, switches an external power source 2 side to an internal power source 5 side, and supplies a power from the internal power source 5 to each part of a disk device 1. Also, the means 3 informs a fact of the power failure to an instructing means 7 in a control means 6, and by this notice, the instructing means 7 issues an instruction to the control means 6, and returns a head 8 to a home position from a position of a designated track. Subsequently, when the head 8 returns to the home position, a switching means 4 is controlled by issuing an instruction to the control means 6, and the power supplied from the internal power source 5 is disconnected. In such a way, such undesirable influence like data loss and disk damage can be prevented.

Description

[Detailed Description of the Invention] [Summary] A disk device used in a small-scale information processing system that does not adversely affect the disk in the event of a power outage during a data writing/successive operation. Regarding the protection system, the purpose is to prevent adverse effects on the disk, and it is designed to protect a disk that rotates by a motor that rotates when the power is turned on, a head that writes/read data to/from the disk, and a head that is connected to a designated device. In addition to controlling the position for positioning on the track on the disk,
In a disk device comprising a control means for controlling data writing/reading, a power failure detection means for detecting a power failure, and a switching means for switching an external power source to an internal power source when the power failure detection means detects a power failure. and instruction means for instructing the control means to position the head at the home position and then cut off the power supplied from the internal power supply when the power failure detection means detects a power failure, When the power supplied to the disk drive from the external power supply fails, it switches to the pre-installed internal power supply to continue supplying power, returns the head from the specified track position to the home position, and then supplies power from the internal power supply. The configuration is such that the power source is turned off.

[Industrial application field]

The present invention relates to a disk device used in a small-scale information processing system, and more particularly to a disk protection method during a power outage that prevents a disk from being adversely affected in the event of a power outage during a data write/success operation.

In recent years, with the development of the information society, small-scale information processing systems such as personal computers and word processors have come into widespread use. In personal computers, word processors, and the like, magnetic disks such as floppy disks and hard disks are frequently used for backing up data.

By the way, although many of these small-scale information processing systems such as personal computers and word processors are designed to handle instantaneous power outages, they are not equipped with measures against power outages, and the If a power outage occurs during a power outage, the data recorded on the magnetic disk may be destroyed or the magnetic disk itself may be damaged.

Therefore, it is necessary to prevent such adverse effects in a magnetic disk device.

[Conventional technology]

In conventional magnetic disk drives that use hard disks, power is also turned on when the information processing system is turned on, but at this time, the head is positioned at the home position of the magnetic disk.
It floats due to the wind pressure generated by the rotation of the magnetic disk. When writing/reading data, the device is positioned at a track specified by the host device and data is written/read.

When the processing of the information processing system is completed, the head is returned to the home position, and then the power of the magnetic disk device is also cut off by turning off the power of the information processing system. Therefore, when the rotational speed of the magnetic disk decreases, the head descends and contacts the home position.

However, if a power failure occurs during a data write/continue operation, the servo control of the head is stopped, so the position of the head on the magnetic disk becomes unstable, but remains approximately on the track being followed. Then, when the rotational speed of the magnetic head decreases, the magnetic head descends and slides after coming into contact with the surface of the magnetic disk. When the power is restored, it slides on the surface of the magnetic disk and then floats up.

Furthermore, in a magnetic disk device that uses a floppy disk, when the floppy disk is inserted, it is fixed to the shaft of a spindle motor and rotates. Then, the head is moved and positioned from the home position to the track position specified by the host device by a step motor that is generally controlled by an oven loop. During data writing/continuation operation, the head load solenoid is driven. The head is touching the specified track.

[Problem to be solved by the invention]

As mentioned above, in magnetic disk drives that use conventional hard disks, when a power outage occurs during data writing/successive data writing, the head descends into the data recording area and slides on the magnetic disk surface, and the power is restored. Then, it floats up after sliding within this data recording area.

Therefore, the noise that enters the head during a power outage and when the power is restored destroys the data recorded in the data recording area of the magnetic disk, and the head slides in an area other than the home position, causing the magnetic disk There is a problem in that the data recording area of the device may be damaged.

In addition, in magnetic disk drives that use floppy disks, if there is a power outage while data is being written/continued, the head is in contact with the track where data is being written/continued. There is a problem in that the data on this track is destroyed due to the mixed noise.

In view of these problems, the present invention aims to prevent adverse effects on disks, such as data destruction and damage to the disk itself, during a power outage.

[Means to solve the problem]

FIG. 1 is a block diagram illustrating the invention in detail.

The disk device 1 operates by being supplied with power from an external power source 2. Therefore, the motor 10 rotates, and the rotation of the motor 10 also rotates the disk 9.

Then, the control means 6 positions the head 8 at a designated track on the disk 9 based on an instruction from a higher-level device (not shown), and writes data sent by the higher-level device or data read by the head 8. is sent to the higher-level device.

The power supplied by the external power supply 2 is supplied to each part of the disk device 1 via the switching means 4, and the power failure detection means 3 monitors the power supplied by the external power supply 2, and controls the switching means 4 when a power failure is detected. Then, the external power source 2 side is switched to the internal power source 5 side, and power is supplied from the internal power source 5 to each part of the disk device 1.

Further, the power failure detection means 3 notifies the instruction means 7 of the control means 6 of the power failure, and upon this notification, the instruction means 7 instructs the control means 6 to move the head 8 from the designated track position to the home position. let it go back When the head 8 returns to the home position, the controller 6 instructs the control means 6 to control the switching means 4 to turn off the power supplied by the internal power supply 5.

[Effect]

With the above configuration, the power to the disk device 1 is cut off after the head 8 returns to the home position, so even if noise is sent to the head 8, the head 8 records data in the data recording area of the disk 9. It does not destroy the data that is currently being used.

Therefore, it is possible to prevent the disk 9 from being adversely affected by a power outage.

〔Example〕

FIG. 2 is a block diagram of a circuit showing one embodiment of the present invention.

When power is supplied from the external power source 2 to each part of the disk device 1 via the switching circuit 12, the motor 10 rotates to rotate the disk 9. The processor 13 reads and operates the program stored in the ROM 14, controls the interface circuit 18, and when it receives an instruction sent from the host device 19 via the interface circuit 18 and input/output capo 15, this instruction is specified. In order to position the head 8 on the track to be
to move the head 8 from the home position.

When using a hard disk, the servo circuit 16 uses servo information to position the head 8 on a track designated by the processor 13, and when the positioning of the head 8 is completed, it notifies the processor 13 that the positioning is complete.

When using a floppy disk, the servo circuit 16 drives, for example, a step motor to move the head 8 in accordance with the number of drive pulses sent out by the processor 13.

When the processor 13 positions the head 8 on the target track, if the command from the host device 19 instructs writing, the processor 13 controls the write/continuation circuit 17 so that the host device 19 sends out the data via the interface circuit 18. write the data to be written. Further, when the command from the host device 19 instructs to read data, the data read by the head 8 is sent to the host device 19 via the interface circuit 18.

For example, the power outage detection circuit 11 monitors the voltage of the power source sent out by the external power source 2 that is input to the switching circuit 12, and when this voltage falls below a predetermined voltage value, the switching circuit 12
For example, by sending a switching signal to external power supply 2,
The internal power source 5 side is switched to the internal power source 5 side, and power is supplied from the internal power source 5.

The internal power source 5 is, for example, a battery installed in the disk unit W1 in advance, and if the external power source 2 is AC, the D
AC power is generated by a C/AC converter or the like and supplied to the primary side of the power supply section (not shown) via the switching circuit 12, or the DC power required by the disk device 1 is supplied to the secondary side of the power supply section. supply to. If the external power source 2 is a DC power source, a DC power source of the corresponding voltage is supplied.

The power failure detection circuit 11 notifies the processor 13 of the power failure of the external power supply 2 via the input/output board 15.
3 controls the servo circuit 16 to return the head 8 to the home position, and also controls the write/read circuit 17 to notify the host device 19 via the interface circuit 18 of the occurrence of an error.

When the processor 13 recognizes that the head 8 has returned to the home position via the servo circuit 16, it controls the switching circuit 12 via the input/output board 15, for example, switches the switch to the external power supply 2 side again, and switches the internal power supply Turn off the power supplied from 5.

FIG. 3 is a flowchart illustrating the operation of the processor of FIG. 2.

FIG. 3 shows processing for a power outage of the external power supply 2.

When the processor 13 receives the power outage detection notification sent from the power outage detection circuit 11 via the human output port 15 as described above in step (3), it instructs the switching circuit 12 to switch the external power source 2 side to the internal power source 5 side. Instructs to switch to .

Then, in step (2), it is checked whether the position of the head 8 is at the home position. When a hard disk is used, the processor 13 recognizes the position of the head 8 from a servo circuit 16 that controls the position of the head 8 in a closed loop using servo information, and when a floppy disk is used, the processor 13 recognizes the position of the head 8 from the servo circuit 16. The position of the head 8 is recognized from the number of step motor drive pulses sent out.

If the position of the head 8 is not the home position, the servo circuit 16 is controlled to move the head 8 in step (2), and the operation of checking whether the position of the head 8 is the home position is repeated in step (2).

When determining that the head 8 is at the home position in step (3), the processor 13 causes the switching circuit 12 to
In step (2), an instruction is given to cut off the power supplied from the internal power supply 5, and the operation is ended.

〔Effect of the invention〕

As explained above, when the power supplied to the disk device from the external power supply fails, the present invention switches to the internal power supply to continue the power supply, returns the head to its home position, and then resumes the power supply from the internal power supply. Since the disc is cut, it is possible to prevent adverse effects such as destruction of the data recorded on the disc or damage to the disc itself.

[Brief explanation of drawings]

FIG. 1 is a block diagram explaining the invention in detail, FIG. 2 is a block diagram of a circuit showing an embodiment of the invention, and FIG. 3 is a flowchart explaining the operation of the processor shown in FIG. In the figure, 1 is a disk device, 2 is an external power supply, 3 is a power failure detection means, 4 is a switching means, 5 is an internal power supply, 6 is a control means, 7 is an instruction means, 8 is a head, 9 is a disk, 10 is a motor , 11 is a power outage detection circuit, 12 is a switching circuit, 13 is a processor, 14
is ROM. 15 is an input/output board, 16 is a servo circuit, 17 is a write/read circuit, 18 is an interface circuit, and 19 is a host device. Anzu 2's professional seven-amp vJ production flowchart

Claims (1)

[Claims] A disk (9) that rotates by being driven by a motor (10) that rotates when the power is turned on, a head (8) that writes/reads data to/from the disk (9), and the head (8). ) in a designated track on the disk (9), and a control means (6) for controlling data writing/reading. , a power outage detection means (3) for detecting a power outage, and when the power outage detection means (3) detects a power outage, an external power supply (
2) to an internal power supply (5); and when the power failure detection means (3) detects a power failure, the head (8) is positioned at a home position with respect to the control means (6). and an instruction means (7) for instructing to cut off the power supplied from the internal power supply (5) after the power supply to the disk device (1) from the external power supply (2) is provided. When the head (8) is returned to the home position from the designated track position, the power supplied from the internal power supply (5) is switched to the pre-installed internal power supply (5) to continue supplying power. Disk protection method during power outage characterized by disconnection.