JPH0452548B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses a disk drive method, in particular, the storage contents of a disk storage medium written by a disk drive device for standard track density are read out by a disk drive device for double track density. This is related to the disk drive system that made this possible.

In general, magnetic disk devices are widely used in computer systems as directly accessible mass storage devices. In particular, flexible disks are relatively inexpensive and easy to handle, so they are widely used even in small systems. Furthermore, as technology improves, the recording density is increasing year by year, and the types are diversifying.

In the past, if a medium was written using a certain type of disk drive device, the contents could only be read by the same type of disk drive device. However, in general, the higher the recording density, the better the cost performance, so the system's disk drive device may be switched to a device with a higher recording density midway through. In this case, the new disk drive cannot read the data written to the original disk drive, so data must be rewritten to the new disk in a system that has both the old and new disk drive. It was hot. Additionally, when attempting to exchange data between multiple computer systems via disks, there was a problem in that all computer systems had to have disk drives of the same device type. . In the case of an existing old computer system, it may not be possible to connect a new disk drive device, and in such cases, data cannot be exchanged via disks.

The present invention aims to solve the above-mentioned problems, and aims to ensure compatibility of disk storage media between disk drive devices that differ only in track density. Therefore, the focus is on manipulating track numbers during seek command processing. Hereinafter, embodiments will be described with reference to the drawings.

FIG. 1 is a diagram for explaining the outline of the present invention, FIG. 2 is a diagram showing the configuration of an embodiment of the present invention, and FIG. 3 is a diagram illustrating processing according to the present invention.

In Figure 1, 1 is double track disk.
A drive device that drives a 5-inch 96TPI flexible disk, for example, 2
3 is a standard track disk drive device which drives, for example, a 5-inch 48 TPI flexible disk; 3 is a flexible disk having storage contents written using the double track disk drive device 1; 4 is a flexible disk drive having storage contents written using a standard track disk drive device 2;
Represents a disk.

The flexible disk 3 has, for example, 80 tracks with track numbers from 0 to 79 on each side. The side of the track is side number 0.
or indicated by 1. One track consists of 16 sectors, and sector positions are indicated by sector numbers from 0 to 15. On the other hand, the flexible disk 4 has 35 tracks with track numbers 0 to 34 on each side. Truck・
The format is the same as that of flexible disk 3.

Conventionally, input/output to the flexible disk 3 was possible only with the double track disk drive device 1, and input/output to the flexible disk 4 was possible only with the standard track disk drive device 2. . The present invention enables a double track disk drive device 1 to read the storage contents of a flexible disk 4 having a track density of 35 tracks on one side.
The track spacing of the flexible disk 4 is approximately twice that of the flexible disk 3. Focusing on this point, track numbers are manipulated during seek as explained below.

In FIG. 2, numerals 1 and 4 correspond to those in FIG. Reference numeral 5 represents a track density analysis section, 6 an address register, 7 a track number conversion section, 8 a multiplier register, 9 a multiplier, 10 an arm, and 11 a magnetic head.

The track density analysis section 5 analyzes the track density of the media mounted on the double track disk drive device 1. Track density analysis is performed, for example, based on density instructions from a program that issues input/output requests. When this density instruction indicates a standard track and the processing request command is a seek command, the track density analysis section 5 sets a multiplier "2" in the multiplier register 8. The multiplier register 8 is normally set to a multiplier of "1" in cases other than the above.

When processing a seek command, the target track number is transferred to the double track disk drive device 1. At this time, the track number stored in address register 6 is input to track number converter 7, and multiplier 9 multiplies the track number by the contents of multiplier register 8. Then, the multiplication result is transferred to the double track disk drive device 1, so if there is a standard track density instruction, the value obtained by doubling the specified track number is supplied as the actual seek track number. That will happen.

The double track disk drive device 1 reads a given track number without being aware of whether the mounted medium is a disk recorded at double track density or a disk recorded at standard track density. Arm 1 in the position corresponding to
Drive and move 0. In the case of the standard track density, the track number is doubled as described above, so the arm 10 moves in units of distance intervals twice the track interval of the double track density, and after the seek is completed, the target A magnetic head 11 is set on a track. Therefore, the contents of the flexible disk 4 can then be read by specifying the sector number, side number, and track number using, for example, a read command.

The track density analysis section 5 and the track number conversion section 7 can be provided in a so-called input/output driver that is provided for each device type and performs input/output processing. Next, an example of processing according to the present invention will be explained with reference to FIG.

When an input/output request is issued to the double track disk drive device 1, the command type is first determined by the process 20 shown in FIG. 3, and it is determined whether the command to be processed is a seek command. If the command is not a seek command, control is transferred to process 25 to process other commands. If it is a seek command, it is determined in step 21 whether the disk mounted on the double track disk drive device 1 is of double track density or of standard track density. . This determination is made, for example, based on a notification from the input/output request source. Alternatively, automatic detection may be performed by appropriate means. If the track density is double, in step 22, the track number notified from the input/output request source is output as is. If the standard track density is
Through the process 23 by the track number converter 7,
The track number notified from the input/output request source is doubled and output. Next, in process 24, the seek
The command is output to drive the double track disk drive device 1.

Commands other than the seek command are processed in the same way as before. For example, if the process 25 recognizes that the processing request command is a read command, the process 26 outputs the track number, side number, and sector number;
Subsequently, in step 27, a read command is output. The same applies to other commands such as write commands.

In the above description of the embodiment, the disk drive apparatus is described as one that processes a track density that is twice the standard track density. Needless to say, it can be extended to

As explained above, according to the present invention, for example, the stored contents of a disk storage medium written by a standard track density disk drive device can be read by a double track density disk drive device. .

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining the outline of the present invention, FIG. 2 is a diagram showing the configuration of an embodiment of the present invention, and FIG. 3 is a diagram illustrating processing according to the present invention. In the figure, 1 is a double track disk drive device, 2 is a standard track disk drive device, 3 and 4 are flexible disks, 5 is a track density analysis section, and 7 is a track number conversion section.

Claims (1)

[Claims] 1 Analyzing the track density of a disk storage medium mounted on a disk drive device for m-times track density in a disk drive system that performs seek operations by moving the magnetic head corresponding to the track number and performs input/output to the disk. If the mounted disk storage medium is a normal track density disk storage medium as a result of the analysis by the track density analysis section and the track density analysis section It is equipped with a track number exchange unit that multiplies the track number by m and outputs it, and by means of a disk drive device for m-fold track density,
A disk drive system that is characterized by being able to input and output data to and from standard track density disk storage media.