JPH03282612A - External auxiliary storage controller - Google Patents

Abstract

PURPOSE:To ensure high speed processing by storing the address information on a passing block with a searching action, etc., when accessing to a desired block, and reading the data information on the passing block based on the address information. CONSTITUTION:A magnetic disk controller 2 receives a multi-sector read command from a host system and starts a reading action. When a block stored in an external auxiliary storage device and to receive an access is searched, the address information on plural passing blocks are stored in an ID register 46 of a format controller 42. Then the data on the passing blocks are sent to the host system based on the stored address information and the address information requested by the host system. Thus it is possible to evade such a defective state where a reading action is delayed owing to a rotation waiting state and to increase the reading speed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a control device for an external auxiliary storage device of an information processing device.

[Conventional technology]

A conventional external auxiliary storage control device will be described using a magnetic disk control device (hereinafter referred to as a control device) as an example.

As a method of controlling a magnetic disk device, there is a method of controlling the magnetic disk device on a sector-by-sector basis.

A sector is the minimum unit for writing and reading data on a disk, which is a storage medium of a magnetic disk device, and one sector has an ID (identification) indicating a logical address of the sector.
f 1cation) and data to be written and read.

The ID is represented by a flag, head number, cylinder number, and sector number.

FIG. 3 shows an outline of the structure of the disk.

The disk 1 is divided into a plurality of concentric tracks 12. Each track is further divided into 16 sectors 13 numbered 0 to 15.

A indicates the position of the head at the start of the read operation, and will be referred to as point A hereinafter. In this example, point A is in the middle of the third sector.

B indicates the starting position of the target sector, hereinafter referred to as point B. In this example, the target sector is sector number 3.

Next, the operation of reading data from the control device will be explained using an example in which the target sector is the third sector.

FIG. 4 is a block diagram showing the configuration of a conventional control device.

In order to read data from a magnetic disk device, reading is performed in units of sectors as described above.

First, a host system (not shown) sets address information of a target sector in the control device 1- and issues a read command. Here, the target sector &,J is the third sector as described above.

A read command from the host system is set in the register 23 via the rewrite controllers 1 to 2 and the multiplexer 22.

In the control device 1 that has received the read command, the processing unit 31 interprets the read command, makes settings within the control device 1, and then starts the format controller 4] and the disk interface controller 24, and starts the read command. Start operation.

In this example, the control device 1 starts the read operation from point A, and first reads the ID of sector No. 4. The read ID is converted into a parallel signal by a serial-parallel conversion circuit 43 in the format controller 41, and then compared by a comparator 44 with the ID of the target sector, that is, the third sector.

The control device 1 determines that the ID of sector 4 is the ID of the target sector.
Since they do not match, the data of the following 4th sector is skipped and the ID of the next sector is waited for.

The control device 1 repeats this operation in sequence until the target sector is reached.

In the following description, the period until the head reaches the target sector due to rotation of the disk will be referred to as rotation waiting.

By waiting for rotation, the head reaches the head position of the target sector, ie, point B, and when the read ID and the ID of the target sector are compared as described above, both IDs match. For the first time here, format controller 4] is 3
Read the data of sector number. This loaded data is data FIF○ (first in first
ara): first = in first-out)
After being temporarily stored in the register 25, the multiplexer 22
transferred to the host system via

When the data transfer is completed, processing unit 3
The error detection and correction circuit II'84.5 checks the state within the control device 1, sets status information in the register 23, and notifies the host system via the multiplexer 22 of the end of the read command.

As described above, conventional control devices sequentially read sector IDs from a magnetic disk device and
If it matched with D, it was closed and the data following the ID was read.

[Problem to be solved by the invention]

The above-described conventional control device has the disadvantage that when performing a multi-sector read, that is, reading a plurality of sectors on a track, data reading becomes slow due to unnecessary rotational waiting.

For example, consider the case of reading from sector 3 to sector 4 to sector 10 (however, in this case as well, the position of the head at the start of the read operation is the same as in the example of the operation explanation above). (assumed to be in the position shown in Figure 3)
.

In this example, the target sector for rotation wait in multi-sector read is sector number 3.

The control device 1 that has received the multi-sector read command,
As described above, after the settings in the control device 1 are made, the read operation is started at point A, and the rotation wait is started.

When the head reaches the head position of the target sector, ie, point B, the read ID matches the ID of the target sector, so the third sector is subsequently read and transferred to the host system.

After the control device 1 finishes transferring the data of sector No. 3 to the host system, it then sets sector No. 4 as the target sector and enters a rotation wait.

In the example shown in FIG. 3, sector interleaving is not performed, so in the next sector, that is, sector No. 4, the ID of that sector matches the ID of the target sector, and the data of sector No. 4 is read.

Repeat the same operation for the 5th sector, the 6th sector...10
Then, the multi-sector read command is completed.

As mentioned above, for example, if the position at which the control device 1 starts the read operation is in the relationship shown in FIG.
...The sectors up to the 10th sector will be read in the second rotation.

That is, the conventional control device has a drawback that reading is slow due to waiting for rotation.

[Means to solve the problem]

An external auxiliary storage control device of the present invention is an external auxiliary storage control device that controls an external auxiliary storage device of an information processing device in units of blocks consisting of address information and data information, and includes blocks to be accessed in the external auxiliary storage device. When searching, the address information of multiple blocks passing through is stored in the address storage section,
The method is characterized in that the data of the passing block is sent to the host system based on the stored address information and address information requested by the host system.

Furthermore, the external auxiliary storage control device according to claim 2 is characterized in that a controllable memory is used as means for storing data information of the passing block.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a first embodiment of the present invention.

As in the operation example of the conventional control device, let us consider the case where reading is performed from the third sector to the fourth sector, . . . to the tenth sector.

The control device 2 receives a multi-sector read command from the host system and starts a read operation, as in the case of conventional control devices. At this time, the I of the sector detected first
D is stored in the ID register 46 in the format controller 42.

In this example, the first sector is sector number 4.

Based on the ID stored in the ID register 46, the processing unit 32 determines whether to store subsequent data in the pig FIFO register 25. In this example,
Recognizing that the stored ID is the ID of the fourth safeter, the data following that ID is stored in the data FIFO register 25. At this time, address information is added before or after the stored data in sector 4 to inform the host system which sector has been read.

After that, the same operation is performed on the 5th sector, 6th sector, etc.
When reading of all sectors specified by the multi-sector read command, starting from sector 10, is completed, the operation ends.

As explained above, in this embodiment, the multi-sector read command ends at the same time as the reading of the data in the third sector ends, so compared to the conventional control device, the data is read from the fourth sector in the second rotation. Sector 5...1
The time required to read sectors up to sector 0 is shortened.

Next, a second embodiment of the present invention will be described.

FIG. 2 is a block diagram showing the configuration of a second embodiment of the present invention.

A second embodiment of the present invention is a data FIF register 2 that stores data in a sector to be read from a magnetic disk device in the first embodiment shown in FIG.
5, it is configured with a data buffer memory 51, and a buffer control circuit 52 having a function of controlling this data buffer memory 51 is added.

The second embodiment operates in the same way as the first embodiment, but in addition, the control functions such as memory address calculation, which were handled by the external host system in the first embodiment, are replaced by buffer control. Since the circuit 52 is in charge, the load on the host system can be reduced compared to the case of the first embodiment.

Further, since data of a plurality of sectors can be stored in advance in the data buffer memory 5, write operations can be performed at high speed.

For example, in a write operation, first, a plurality of sectors of pigs are stored in the pig buffer memory 51 in advance. Next, the buffer control circuit 52 calculates a memory address based on the address information read from the magnetic disk device and stored in the ID register 46. Next, based on the memory address resulting from this calculation, the data information of the corresponding sector is read from the data buffer memory 51 and written to the magnetic disk device.

By doing this, commands that use data from the host system, such as read commands such as verify and write commands, which would be difficult to implement in the first embodiment because the load on the host system would be too large. Also, high-speed processing is possible.

Although a magnetic disk control device has been described as an example here, as is clear from the above description, the present invention is applicable not only to magnetic disk control devices but also to external auxiliary storage control devices that control floppy disks, optical disks, etc. Needless to say, it can also be applied to

〔Effect of the invention〕

As explained above, according to the present invention, when accessing a target block, address information of the block passed through by search etc. is stored, and based on this address information,
It is possible to read the data information of the passing block that was skipped by the conventional external auxiliary storage controller, which eliminates the disadvantage of the conventional external auxiliary storage controller that reading is slow due to waiting for rotation. and can be loaded quickly.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a first embodiment of the invention, FIG. 2 is a block diagram showing the configuration of a second embodiment of the invention, and FIG. 3 shows a disk of a magnetic disk device. FIG. 4 is a block diagram showing the structure of a conventional magnetic disk control device. 1. 2.3...Magnetic disk control device, 1]...Disk, 12...Track, 13...Sector, 21
...Read/write controller, 22...Multiplexer, 23...Register, 24...Disk interface controller, 25...Data FIFO register, 31.32...Processing units 1 to 3 41.42... Format controller, 43...
・Serial parallel conversion circuit, 44... comparator,
45...Error detection and correction circuit, 46...ID register, 51...Data buffer memory, 52...Buffer control circuit.

Claims (1)

[Claims] 1. In an external auxiliary storage control device that controls an external auxiliary storage device of an information processing device in units of blocks consisting of address information and data information, a block to be accessed in the external auxiliary storage device is searched. When passing, address information of a plurality of blocks to be passed is stored in an address storage section, and data of the passing blocks is sent to the host system based on the stored address information and address information requested by the host system. An external auxiliary storage control device characterized in that: 2. The external auxiliary storage control device according to claim 1, wherein a controllable memory is used as means for storing data information of the passing block.