JPS62245578A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To simplify the software of a host and reduce the burden of the host by transmitting a single command from the host irrespective of the position of a cylinder and automatically seeking to a shipping area. CONSTITUTION:A logic control circuit 30, after the initialization, when a magnetic head is moved to a cylinder number '0', resets an up/down counter 34 by making a detection signal from the track 0 sensor of a disk enclosure part a head reset signal 58. Thereafter, the head is positioned on the designated cylinder by a seeking direction designating signal 54 and a stepping number designating signal 55 from the host device, every time thereof, the respective signals are inputted to the counter 34 and the contents thereof indicate the final cylinder number. When the seeking operation command to the shipping area is carried out to all disk devices from the host, the larger number than the cylinder number of the data area of the disk device is applied as a signal 55 and a processing circuit 40 subtracts the cylinder number in the counter 34 from the cylinder number of the shipping area to supply to the circuit 30.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention allows a magnetic head to float above the surface of a magnetic disk when a magnetic disk is rotating.

The present invention relates to a so-called contact start/stop (Cps) type magnetic disk drive in which a magnetic head comes into contact with the surface of a magnetic disk and stops when the rotation of the magnetic disk is stopped.

[Conventional technology]

In recent magnetic disk drives, when the magnetic disk is not rotating, the magnetic head comes into contact with the surface of the magnetic disk and stops, and when the magnetic disk rotates, the airflow generated by this causes the magnetic head to move to a predetermined height. It floats to the surface and writes information (WR-iTE) and puts out the wire 1 (・EA
, D) i) is the mainstream.

A magnetic disk device of this type (referred to as C8S type) has four magnetic disks, as illustrated in FIG.
Outside or inside the information storage area 40a in the storage plane of 0 (
In the example shown in Fig. 2, a shipping area (CSS) 40b'i (also referred to as an inner side) is provided, and when the rotation of the magnetic disk is to be stopped, the magnetic head moves (seeks) to this shipping area 40b and moves to the shipping area 40b'i. means are used. This is because if the C8S operation is performed within the information storage area, the storage VF information may be destroyed (head crash) due to contact between the magnetic head and the magnetic disk.

However, due to the structure of small magnetic disk devices, especially devices that use a stepping motor to drive the magnetic head, when the power is completely cut off and the rotation of the magnetic head is stopped, the magnetic head is automatically moved up to the shipping area. = It is difficult to make it work. Therefore, in order to achieve this purpose, when power is expected to be cut off, it is necessary to perform a seek operation cc from the host device to the shipping area in advance.
88 zone return operation), but CSS
The cylinder number to which the magnetic head is positioned immediately before the zone return operation is undefined. Therefore, if multiple magnetic disk devices are connected to the same host,
The host must command a different number of cylinder seek operations for each valley magnetic disk device. Therefore, the host software for this becomes complicated and the burden on the host becomes heavy.Also, if there is a bug in the software, a complete C8S zone return operation will not be performed and a head crash will occur. There is also a risk that the seven isles of important information may be destroyed.

Figure 3 shows an example of such a conventional magnetic disk device (N
EC Technical Report vol, 38. No, 7. (See pages 17 to 21), and FIG. 4 is a flowchart showing the operation of the example shown in FIG. 3.

Is the conventional magnetic disk referring to Figures 3 and 4? A
An overview of the configuration and operation of lt will be explained below.

The interface unit 2 sends and receives information and control signals to and from a higher-level device (host) via the disk control device 23. The logic control circuit 3 is composed of one dedicated LSI, and has a step signal processing register/register, a timing generation circuit and register for the embedded servo, and an access port to the two processing circuits 4 and 5. There is. The processing circuit 4 is a circuit that controls the entire magnetic disk drive, such as processing interface signals and controlling the royal solenoid and spindle motor, and includes a microprocessor (μp) 21 and a read-only memory that stores all its operating instructions. The processing circuit 5 is a dedicated circuit for controlling the positioning operation of the magnetic head, and detects the embedded servo signal, controls the positioning motor, and processes the micro This is done by processor. Disk enclosure section (D
Ei) 8 is a read/write amplifier circuit (R, /WIC)-
i magnetic head (hereinafter simply referred to as 4-mi head) 11
12% of the positioning motor that moves the entire positioning operation.
This is a mechanical unit in which a spindle motor 15, etc., which mounts a magnetic disk and drives rotational movement for positioning the disk, is housed in a sealed container. The positioning motor 12 is controlled by the processing circuit 5 via the positioning motor driver 6, and the spindle motor 15 is controlled by the slot/driver motor driver 7.
It is controlled by the logic control circuit 3 via the logic control circuit 3. The write data from the host device is sent to the write data data signal (WE, ITE DATA) 6 via the interface section 2.
2 is sent to the magnetic disk 11 and written on the magnetic disk. On the other hand, the data signal of the 'fc information read out by the magnetic helad 11 is modulated into a digital signal by the read circuit 9 and is read out as a read data signal (R, EAD DATA).
63, it is sent to the host device through the interface section. Further, among the information read by the magnetic head 1, servo information is converted into a digital signal by the AD conversion circuit 10 and sent to the logic control circuit 3.

The magnetic disk device 1 configured as described above operates as shown in the flowchart of FIG. 4.

That is, first, when the power of the magnetic disk device 1 is turned on (reference numeral a), a so-called initialization operation (reference numeral b) in which the troughs of the control circuit return to the initial state occurs (reference numeral b). At the same time as doing
When the spindle motor 15 rotates and its rotational speed reaches a predetermined value, it sends out a ready signal (READY) 60' (r). Upon receiving this READY60, the host device sends a drive selection signal (DR, IVESLECT) to the host device. The magnetic disk device sends a signal 53 to select all desired devices from among the plurality of magnetic disk devices.
53 (reference numeral C), it sends out a drive selection completion signal (DRI-VE 8ELECTED) 61 and receives the next signal.

The next signal is the write gate signal (WRITE GATE)
In the case of 52 (reference code d), the write operation (reference code e) is performed by the write data signal (Wl (, ITE DATA) 62 sent at the same time) in row 9° WRITEG.
If ATE 52 is empty and the primary signal step number designation signal (STEP: signal that specifies the number of cylinders to be moved during seek operation of the magnetic head) 55 is empty (reference symbol f), read All operations and other processing operations are performed (reference numeral g).

If 8TEP55 is exhausted, an operation (seek operation) is performed to move the magnetic head to a cylinder position different from the current position. In this case, they will be sent at the same time. Depending on the state of the seek direction designation signal (DIRECTIO1'J IN) 54! 1ll (reference number h), when the cylinder is active, seek in the inner circumferential direction (reference number 1. When inactive, perform a seek operation in the outer circumferential direction (reference mark i) for the specified number of cylinders. When the seek operation is completed, the seek operation completion signal (8EEK
COMPLE'I'B) 59 is sent, all predetermined magnetic heads are selected by the head selection signal (HEA, D5ELECT) 51, and a write data signal (WRI'l'BDATA) 62 is written on the corresponding track. Perform an action or read stored information from that track. Once the magnetic helad 11 is positioned on any cylinder, the primary is moved directly from that cylinder onto the next designated cylinder. Therefore, if multiple magnetic disk devices are connected to the host device.

Since magnetic disk drives operate independently of each other, when you try to turn off the power all at once.

In each magnetic disk device, the cylinder position where the magnetic head is finally positioned is not constant.

Therefore, in order to move all magnetic disk devices to the shipping zone, the host must specify the number of steps and seek direction for each magnetic disk device individually. The host's software becomes complex, and the burden on the host is also large.

[Problem that the invention seeks to solve]

Problem 4 to be Solved by the Present Invention In other words, an object of the present invention is to eliminate the drawbacks of the conventional magnetic disk drive as described above, and to provide a simple solution regardless of the position of the cylinder in the magnetic disk drive. By sending one command from the host, each magnetic disk device can automatically seek from its current position to the shipping area, simplifying the host's software system and burdening it. The object of the present invention is to provide a complete magnetic disk device that can reduce the amount of stress.

[Means for solving problems]

The magnetic disk device of the present invention inputs an input signal including a seek direction designation signal and a step number designation signal from an interface section that sends and receives information to and from a host device, and outputs an output signal including a head return signal to the interface section. In the magnetic disk device, the magnetic disk drive includes a logic control circuit that sends out all signals, and a processing circuit that sends and receives information to and from the logic control circuit and performs processing operations to control the operation of the disk mechanism section. A logic control circuit includes an inverter that inputs the seek direction designation signal and inverts its polarity, a first AND circuit that uses the output signal of the inverter, the step number designation signal, and all input signals, and the seek direction designation signal. a second AND circuit whose input signals are the signal and the step number designation signal; the output signal of the first AND circuit is inputted to a countdown terminal; and the output signal of the second AND circuit is inputted to a countup terminal. The head return signal i is input to the 1J set terminal and outputted from an up/down counter connected to the processing circuit, and the processing circuit determines the magnitude of the step designation signal and the number of data areas of the magnetic disk. If the step designation signal is larger than the number of data areas, the contents are read from the up/down counter and the value of the weight/r is subtracted from the cylinder number of the shipping area of the magnetic disk to generate all the value direction designation signals. It consists of a dedicated circuit for storing a series of commands to be sent out.

〔Example〕

Next, embodiments of the present invention will be described in detail with reference to one drawing.

FIG. 1 is a block diagram showing the main parts of an embodiment of the present invention.

In this embodiment, as shown in FIG. 1, inverter triple AND circuits 32 and 33 and an up/down counter 34 are added to the logic control circuit 30, and these are used in the R (JM) of the processing circuit to cover the entire shipping area of the magnetic head. Contains movement instructions for automatic fertilization.

A seek direction designation signal (D
IRECTION IN) 51 is input to one input terminal of the AND circuit 32 via the inverter 31 and directly to one input terminal of the AND circuit 33. On the other hand, the step number designation signal 55 is directly sent to the AND circuit 3.
The signals are input to the other input terminals 2 and 33. The output signal of the AND circuit 32 is input to the count-down terminal of the up-down counter 34, and the output signal of the AND circuit 33 is input to the count-up terminal U of the up-down counter 34. Also, head return signal (TRACKO) 5
g is input to the reset terminal R of the up/down counter 34. The contents of the up/down counter 34 are stored in the processing circuit 4.
0 microprocessor (μP) 41.

The logic control circuit 30 configured as described above.

As described above, it is initialized when the power is turned on. Subsequently, when the magnetic head is moved to cylinder number "'O", the detection signal 64 sent from the track 0 sensor 14 (see Figure 3) of the DE section is inputted to generate a head return signal (TRACK). 0) Interface part 2 as 5B
This is then branched to up/down cuff/re3.
Input to the reset terminal R of No. 4 to reset all of them. After this, DIRECTION 1N54 and 5TEP 55 are sent from the host device to position the magnetic head on the specified cylinder, but each time these are input to the alarm down counter 34, the up-down is performed. The contents of the down counter always indicate the last cylinder number in which the magnetic head was positioned.

In such a state, it is predicted that the power will be cut off, so when the host instructs all magnetic disk devices to seek to the shipping area, the procedure shown in the flowchart in Figure 5 is used. .

In FIG. 5, processing operations a-b-c-g and judgment operations c
The operation up to -df is the same as the conventional case described above, but
When issuing a seek operation command to the shipping area, 5TE
The contents of the P signal are different.

That is, in this case, a number greater than the number of cylinders in the data area of the magnetic disk drive (usually the number of cylinders in the data area + 1) is given as the 5TEP signal. Processing circuit 4
0 determines this (reference code k), calculates the contents from the up-down counter, that is, the cylinder number where the magnetic head was last positioned + m, and performs logical control to subtract the value of the up-down counter from the cylinder number in the shipping area. The logic control circuit generates a 5 TEP signal and a DIRECTION signal with a number of pulses corresponding to this value, and drives the positioning motor 12 (reference numerals m and n) to move the magnetic head to the shipping area. .

If the 5TEP signal is smaller than the number of cylinders in the data area, a normal seek operation is being commanded, and as always, a seek operation is performed in the inner or outer direction depending on the presence or absence of DII'LBC'I'ION IN.

〔Effect of the invention〕

As explained in detail above, by using the 8-speed disk device of the present invention, when a plurality of magnetic disk devices are connected to a host, the host can simply issue the same command to each magnetic disk device. Since each seek operation is performed for the required number of cylinders, the software of the host can be simplified, and at the same time, the burden on the host can be completely reduced.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the main parts of an embodiment of the present invention;
FIG. 2 is an explanatory diagram showing an example of dividing the area of a magnetic disk, FIG. 3 is a block diagram showing an example of the configuration of a conventional magnetic disk device, and FIG. 4 is a flowchart showing the operation of the example in FIG. 3. FIG. 5 is a 70-chart showing the operation of the embodiment of FIG. In the figure, 3...logic circuit, 31...inverter, 32.

Claims (1)

[Claims] An input signal including a seek direction designation signal and a step number designation signal is inputted from an interface unit that transmits and receives information to and from a host device, and an output signal including a head return signal is sent to the interface unit. In a magnetic disk drive comprising a logic control circuit that transmits data, and a processing circuit that transmits and receives information to and from the logic control circuit and performs a processing operation to control the operation of a disk mechanism section, the logic control circuit comprises: , an inverter that inputs the seek direction designation signal and inverts its polarity; a first AND circuit that receives the output signal of the inverter and the step number designation signal as input signals; and a first AND circuit that receives the seek direction designation signal and the step number designation signal. a second AND circuit which receives the number designation signal as an input signal; the output signal of the first AND circuit is inputted to a countdown terminal; the output signal of the second AND circuit is inputted to a countup terminal; and the head is restored. an up/down counter inputting a signal to a reset terminal and having an output signal connected to the processing circuit, the processing circuit determining the magnitude of the step designation signal and the number of data areas of the magnetic disk; If the step designation signal is larger than the number of data areas, the contents are read from the up/down counter, a step pulse of the value obtained by subtracting the value of the counter from the cylinder number of the shipping area of the magnetic disk is sent, and at the same time, the seek A magnetic disk device characterized by comprising a read-only circuit that stores an instruction at one end for creating and transmitting a direction specifying signal.