JPH03266268A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To eliminate the difference of the error rates of the inner and the outer peripheries of a magnetic disk by setting a first and a second reading.writing means according to the inner and the outer peripheries of the magnetic disk. CONSTITUTION:A read.write circuit 4a and a servo circuit 5a are adjusted previously into a set value for the outer periphery, and the read.write circuit 4b and the servo circuit 5b of the circuit configuration of an inner periphery side are adjusted previously into the set value for the inner periphery. Then, when a host computer 1 transmits a seek instruction to an interface 3, the interface circuit 3 interprets the instruction, and decides to which of the inner or the outer periphery of the magnetic disk 10a to 10d the magnetic head 9a to 9h is to be moved. Thus, by providing a pair of the reading.writing means to write and read information correspondingly to the inner and the outer peripheries of the magnetic disk 10a to 10d, these reading.writing means are adjusted to different set values for the inner and the outer peripheries of the magnetic disk, and the difference of the error rates of the inner and the outer peripheries of the magnetic disk is suppressed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetic disk device, and more particularly to a magnetic disk device having first and second read/write means corresponding to the inner and outer peripheries of a magnetic disk, respectively. It is related to.

[Prior art] Figure 3 shows, for example, "Mitsubishi Electric Techniques Vol. 58 No.
, 2/1984'' is a schematic configuration diagram showing a conventional magnetic disk device. In the figure, (1) is the host computer, and (2) is this host computer (1).
(3) is a host computer (
1) an interface circuit that mediates the transmission and reception of information with the
(4) is a read/write circuit that demodulates a read command when it receives it from the host computer (1) via the interface circuit (3), and modulates it when it receives a write command; and 5) the host computer (1). A servo circuit for controlling the position of the magnetic head to the track on the magnetic disk designated by the seek command upon receiving a seek command from the interface circuit (3);
6) is an enclosure for fixing and densely mapping the circuits (9) to (11) described later, and (7) is a servo circuit (5).
), (8) is an actuator driven by actuator motor (7), (9a) to (9d) are actuator motors (8)
) for electromagnetically converting the data supplied by the read/write cycle #I (4), (10
a) to (10d) are magnetic heads (9a) to (9), respectively.
(11) is a magnetic disk for storing data electromagnetically converted by (d), magnetic disks (10a) to (1);
0d) is a spindle motor for fixing and rotating the motor.

Next, the operation of the conventional magnetic disk device shown in FIG. 3 will be explained. In the magnetic disk device (2), information is written on the circumference of the magnetic disk (9) called tracks, which are divided by concentric circles. As long as the information (data) transfer speed is the same, the inner circumference and outer circumference of the magnetic disk (9) have different circumferential lengths, so the storage density in the circumferential direction (BPIBit Per Inch) is different.

Now, we will explain the reading operation when information is written on any of the above-mentioned tracks. First, the host computer (1) sends a magnetic card (9) to the track where information is written. A seek command for movement is sent to the interface circuit (3) in the magnetic disk device (2). The interface circuit n(3) interprets the command and transmits the moving direction and distance as data to the servo circuit (5). The servo circuit (5) controls the actuator motor (7) based on the data and drives the actuator (8). A magnetic head (9) fixed to an actuator (8) electromagnetically converts the current position information written on the magnetic disk (10) and sends it to the read/write circuit (4), which transmits the information to the servo circuit (5). )
The magnetic head (9) is controlled by feedback to move the magnetic head (9) to the desired track position. When this seek command is completed, the host computer (1) issues a read command to read information from the interface F! #
1 (3) to the read/write circuit (4). The read/write circuit (4) selects one magnetic head from the magnetic heads (9a) to (9d) according to the read command, demodulates the information electromagnetically converted to the selected magnetic head, and sends the information to the interface circuit. (3) The information is sent to the host computer (]) to complete the series of reading operations. In addition, in the write operation, similarly to the read operation described above, after the seek command is completed, a write command for writing information is sent from the host computer 1) to the read/write circuit (4) via the interface circuit (3). . The read/write circuit (4) modulates information according to a write command, selects one magnetic head from the magnetic heads (9a) to (9d), and sends current to the selected magnetic head to write to a track on the magnetic disk. Write the information and complete the series of write operations.

[Problems to be Solved by the Invention] As described above, in conventional magnetic disk drives, although the storage density in the circumferential direction differs between the inner and outer circumferences of the magnetic disk, the position of the magnetic head is the same on both the inner and outer circumferences. Since the read/write circuit and servo circuit are adjusted according to the set value, there were problems such as high error rates on the inner and outer circumferences of the magnetic disk.

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to obtain a magnetic disk device in which the difference in error rate between the inner and outer circumferences of the magnetic disk is small.

[Means for Solving the Problems] A magnetic disk device according to the present invention includes: a host computer; a first read/write device connected to the host computer and having a circuit constant for the outer circumference of the magnetic disk; The second read/write means is connected to a host computer and has circuit constants set for the inner circumference of the magnetic disk, so that different servo control can be performed on the inner and outer circumferences of the magnetic disk.

"Function" In this invention, by providing a pair of read/write means for writing and reading information corresponding to the inner and outer circumferences of the magnetic disk, these read/write means can set different settings on the inner and outer circumferences of the magnetic disk. This value is adjusted to suppress the difference in error rate between the inner and outer circumferences of the magnetic disk.

Embodiment 1 An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a configuration diagram showing one embodiment of the present invention, and (1) to
11 is the same as described above.

In addition, the circuits (4), (5), (7) to (9), etc. are each 1
They are distinguished by subscripts abc, . . . , etc. Here, read/write circuit (4a), servo circuit (
5a), the actuator motor (7a), the actuator (8a) and the magnetic heads (9a) to (9d) are the first
constitutes read/write means for read/write times f? fi
(4b), servo circuit (5b), actuator motor (7b), actuator (8b) and magnetic head (9
e) to (9h) constitute the second read/write means. Moreover, FIG. 2 is a plan view of FIG. 1 partially viewed from above.

Next, the operation of the embodiment of the present invention shown in FIG. 1 will be explained. First, adjust the read/write circuit (4a) and servo circuit (5a), which are the circuit configuration on the outer circumference side, to the setting values for the outer circumference, and then adjust the read/write circuit (4b) and servo circuit (5b), which are the circuit configuration on the inner side. Adjust the setting value for the inner circumference.When the host computer (1) sends a seek command to the interface (3), the interface circuit (3) interprets the command and moves the magnetic head (9) to the magnetic disk (10). ) to the inner or outer circumference of the magnetic disk (10).If the magnetic head (9) is located on the inner circumference of the magnetic disk (10),
If you have to seek e) to (9h),
The configuration of the circuit and device for the inner circumference, that is, the second read/write means is selected, and read/write operations are performed in the same manner as in the conventional method. Furthermore, if it is necessary to seek the magnetic heads (9a) to (9d) on the outer periphery of the magnetic disk (10), the configuration of the circuit and device for the outer periphery, that is, the first
The read/write method is selected and the read/write operation is performed using the same method as before.

FIG. 2 shows an example of the mechanical realization of this invention.
For example, an actuator for the outer circumference with a short arm (8a) and an actuator for the inner circumference with a long arm (8b) on the opposite side.
Place. This arrangement may be at any position on the circumference -E of the magnetic disk (10) as long as there is no conflict in the movable range of the arms.

Further, when the actuator motors (7a) and (7b) are linear motors, they are arranged close to each other.

The error rate is the circumferential storage density (BPI) mentioned above.
In addition to the storage density between tracks (TP T =Track
Per Inch).

As long as the transfer rate of BPI information is constant, the error rate is higher on the inner circumference of the magnetic disk, so the error rate on the inner circumference of the magnetic disk is worse than the error rate on the outer circumference of the magnetic disk. However, if the actuators are separated at the inner and outer circumferences of the magnetic disk as described above, different servo control can be performed at the inner and outer circumferences of the magnetic disk, so there is no problem even if the TPT is changed at the inner and outer circumferences of the magnetic disk. That is, it is possible to reduce the error rate 1- on the inner circumference side of the magnetic disk by lowering the TPT by the amount that the BPI becomes higher on the inner circumference side of the magnetic disk. Alternatively, it is possible to increase the storage capacity by increasing the TRI on the outer circumferential side of the magnetic disk.

In the above embodiment, the read/write means is arranged in one pair on the inner and outer peripheries of the magnetic disk, or even if there are multiple pairs of read/write means, they do not lie side by side. In this case, the range of l/racks to be divided is increased, and it goes without saying that servo control with no difference in error rate between the inner and outer circumferences of the magnetic disk can be performed.

[Effects of the Invention] As described above, according to the present invention, a host computer, a first read/write means connected to the host computer and having circuit constants for the outer periphery of a magnetic disk set, and a first read/write means connected to the host computer, A second read/write means is connected to the magnetic disk and has circuit constants set for the inner circumference of the magnetic disk, and different servo control can be performed on the inner and outer circumferences of the magnetic disk, so there is no difference in error rate between the inner and outer circumferences of the magnetic disk. This has the effect of providing a magnetic disk device free of clutter.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a plan view partially viewed from above of FIG. 1, and FIG. 3 is a block diagram showing a conventional magnetic disk device. In the figure, (1) is a host computer, (2) is a magnetic disk device, (4) is a read/write circuit, 5 is a servo circuit, (7) is an actuator motor, (8) is an actuator, and (9) is a magnetic head. , (10) are magnetic disks. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] A host computer; A first read/write means connected to the host computer and having circuit constants set for the outer circumference of the magnetic disk; A first read/write means connected to the host computer and having circuit constants for the outer circumference of the magnetic disk; 1. A magnetic disk device, comprising: second read/write means having circuit constants set for the magnetic disk, and capable of performing different servo control on the inner and outer circumferences of the magnetic disk.