JPH0554527A - Disk device - Google Patents

Abstract

(57) [Abstract] [Purpose] Starting of a disk drive motor 14 in a disk device provided with a plurality of disk drives for rotationally driving a disk as a recording medium, for example, an FDD device provided with two FDDs 1 and 2. Inrush current is reduced. [Configuration] Motor-on delay time setting in which delay times for delaying the timing of starting the motor 14 are set to different times in the FDDs 1 and 2 with respect to the timing when the motor-on signal instructing to drive the motor 14 from the host device 4 is activated The section 16 is provided. The CPU 12 that controls the drive of the motor 14 controls the start timing of the motor 14 according to the signal of the setting result by the delay time setting unit 16. As a result, the start-up timing of the motors 14 of the FDDs 1 and 2 can be shifted, and the inrush current at the start-up can be greatly reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk device, and more particularly to a disk device provided with a plurality of disk drives for rotationally driving a disk as a recording medium to write information to and read information from the disk. is there.

[0002]

2. Description of the Related Art Conventionally, a system such as a personal computer or a word processor may be provided with a plurality of FDDs (floppy disk drives) for writing and reading information to and from a floppy disk as a magnetic recording medium. In this case, a plurality of FDDs are connected by, for example, a daisy chain method, and when the motor-on signal input from the host device becomes active, each FDD is activated.
The disk drive motor that rotationally drives the DD disk was started at the same time.

[0003]

However, in the system driven by the battery in the system having the above-mentioned structure, when the disk drive motors of a plurality of FDDs are simultaneously activated in a state where the battery capacity is small, in that case. Since the inrush current is large, the power supply voltage may drastically drop, and the system may be reset and the system may go down. Further, in that case, there is a problem that the life of the battery of the power source is substantially shortened.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a structure capable of reducing the inrush current at the time of starting the disk drive motors of a plurality of drives in a disk device having a plurality of disk drives as described above.

[0005]

In order to solve the above problems, according to the present invention, in a disk device of the type described above, a motor-on signal for instructing the drive of the disk drive motor of each disk drive is activated from the host device. Means for setting the delay time for delaying the timing for starting the disk drive motor to a different time in each disk drive, and the start timing of the disk drive motor for each disk drive according to the setting result by the setting means. The structure which provided the means to control was adopted.

[0006]

According to this structure, the rush current at the time of start can be reduced by shifting the start timing of the disk drive motor of each disk drive according to the motor-on signal.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. Here, an FDD device including two FDDs is illustrated.

FIG. 1 shows the configuration of the control system of the FDD device of the embodiment. The FDD device of this embodiment has first and second FDDs.
It is composed of DDs 1 and 2 and is connected to a host device 4 such as a word processor or a personal computer via an interface circuit 3. The configurations of the FDDs 1 and 2 are common, and the configuration of the illustrated FDD 1 will be described here.

In the structure of the FDD 1, reference numeral 12 is an FD.
CPU consisting of a microprocessor that controls the entire D
(Central processing unit), which is driven by a clock signal supplied from the oscillation circuit 11.

Reference numeral 13 is a motor drive circuit which drives the disk drive motor 14 under the control of the CPU 12, and drives the motor 14 when the motor drive signal output from the CPU 12 is active.

Reference numeral 15 is a memory of a storage means used in the CPU 12, and a part of the storage area is the motor 14.
Is used as an MTR (motor on register) 15a that indicates whether or not is on (driven). Here MT
When the data of R15a is "1", it indicates that the motor 14 is on, and when it is "0", it indicates that it is off.

Reference numeral 16 is a motor-on delay time setting unit (hereinafter abbreviated as "delay time setting unit"), which operates the motor 14 in response to a timing when a motor-on signal for instructing the motor 14 from the host device 4 is activated. This is a circuit for setting a delay time for delaying the timing of actual activation to 0 or a predetermined time T (≠ 0). The output signal of the delay time setting unit 16 is input to the CPU 12.

The delay time setting unit 16 is composed of a switch 16a and a pull-up resistor 16b as shown in FIG. 2, for example. When the switch 16a is turned on or off, the output signal of the delay time setting unit is "0". “(Low level of ground) or“ 1 ”(High level of power supply voltage Vcc). The output signal of the delay time setting unit 16 is set by FDD.
1 and 2, for example, the delay time setting unit 16 of the FDD 1
Is output as "0", and the output of the delay time setting unit 16 of the FDD 2 is set as "1". The CPU 12 determines the delay of the start timing of the disk drive motor 14 according to the level of the input signal from the delay time setting unit 16 as described later.

With the above configuration, when the motor-on signal input from the host device 4 to the CPU 12 via the interface circuit 3 becomes active, the CPU 12 activates the motor 14, and details of the control in that case will be described. Three
This will be described below with reference to the flowchart of FIG.

In the control of FIG. 3, first, in step S1, it is determined whether the motor-on signal is "1" (active). When it is "0", the process branches to step S7 and the MTR15
After the data of a is set to "0", the process jumps to step S6 and the processes other than the starting process of the motor 14 are performed.

On the other hand, if the motor-on signal is "1" in step S1, the process proceeds to step S2 to judge whether the data of the MTR 15a is "1". If "1", the motor 14 is already on. Since it means that, the process jumps to step S6 to perform other processing.

When the data of the MTR 15a is "0" in step S2, it means that the motor 14 is not turned on yet. Therefore, in step S3, the MTR is set to "1" and the delay time is set. It is determined whether the input signal from the unit 16 is "0" or "1".

If it is "0", the process proceeds to step S5 and the motor drive signal is immediately activated to activate the motor 14
Is started, that is, the delay time is set to 0, but in the case of "1", after the delay processing of waiting for the predetermined delay time T (≠ 0) by the software timer in step S4,
In step S5, the motor 14 is started.

After step S5, after other processing is performed in step S6, the process returns to step S1.

According to such control, the FDD1,
By setting the outputs of the delay time setting unit 16 of No. 2 to "0" and "1" respectively, the motor-on signal from the host device 4 becomes active ("1") as shown in the timing chart of FIG. FDD1 at time t1
However, the disk drive motor 14 of FDD2 is started at time t2 after a predetermined delay time T has passed from time t1.

That is, since the start timings of the disk drive motors of the FDDs 1 and 2 are shifted by the time T, the rush current at the start of the motors is greatly reduced as compared with the conventional one, and the sudden load increase of the power source is greatly alleviated. It Therefore, especially when the power source of the apparatus is a battery, it is possible to prevent the system from being down at the time of starting the disk drive motor, and it is possible to substantially extend the life of the battery of the power source.

Of course, the relationship between the outputs "1" and "0" of the delay time setting unit 16 and the setting of the delay time of the start timing of the motor 14 may be reversed.

Of course, the number of FDDs provided in the device is not limited to two, and three or more may be used. In that case, the types of output signals of the delay time setting unit 16 should be three or more, and the respective FDDs should be provided accordingly. Set different delay time of motor start timing. In this case, the difference in delay time does not have to be uniform and may be changed.

By the way, in a system in which a plurality of FDDs are provided, each FDD is generally numbered with an identification number, such as drive 0, drive 1, ..., And means for setting the identification number is provided in the system. Be done. If this setting means is also used as the delay time setting unit 16, the delay time setting unit 16 is not newly provided, and the cost is not increased accordingly.

In the control of the flow chart of FIG. 3, the timing of the delay processing in step S4 is performed by the software timer, but it goes without saying that a timer circuit such as a one-shot circuit may be used in hardware. ..

The delay time setting unit 16 need not be a switch, and the delay time may be set by replacing the jumper pin 16c on the circuit board as shown in FIG. 5, for example.

[0027]

As is apparent from the above description, according to the present invention, in a disk device having a plurality of disk drives, a motor-on signal for instructing the drive of the disk drive motor of each disk drive is activated from the host device. Means for setting a delay time for delaying the timing for starting the disk drive motor to a different time in each disk drive, and the start timing of the disk drive motor for each disk drive according to the setting result by the setting means. Since the control means is provided, it is possible to significantly reduce the inrush current at the time of starting the disk drive motor by shifting the start timing of the disk drive motor of each disk drive according to the motor-on signal. Therefore, particularly when the power source of the device is a battery, it is possible to prevent the problem that the system of the device is down due to a sudden load increase of the power source of the device at the time of starting,
Further, excellent effects such as substantially extending the life of the battery of the power source can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a control system of an FDD device according to an embodiment of the present invention.

2 is a circuit diagram of an embodiment of a motor-on delay time setting unit 16 in FIG.

FIG. 3 is a flow chart diagram of start-up control of a disk drive motor by a CPU 12 in FIG.

FIG. 4 is a timing chart showing the deviation of the start timing of the disk drive motor.

5 is a circuit diagram of another embodiment of the motor-on delay time setting unit 16 in FIG.

[Explanation of symbols]

 1, 2 FDD 3 interface circuit 4 host device 12 CPU 13 motor drive circuit 14 disk drive motor 15 memory 16 motor-on delay time setting unit

Claims (2)

[Claims] 1. In a disk device provided with a plurality of disk drives for rotationally driving a disk as a recording medium, at a timing when a motor-on signal for instructing driving of a disk drive motor of each disk drive is activated from a host device. On the other hand, there are provided means for setting a delay time for delaying the timing of starting the disk drive motor to a different time for each disk drive, and means for controlling the start timing of the disk drive motor of each disk drive according to the setting result by the setting means. A disk device characterized by the above. 2. The disk device according to claim 1, further comprising means for setting an identification number of each disk drive, wherein the setting means is also used as the delay time setting means.