JPH0528667A - Magnetic disk control part - Google Patents

Abstract

PURPOSE:To prevent the waiting rotation of a magnetic disk device from entering by a correction processing when a correction possible ECC error exists in read data from the magnetic disk device. CONSTITUTION:An inner part memory 40 storing data belonging to an ECC part for the portion of required one transfer sector number is provided and read data belonging to the ECC part read from the magnetic disk device 200 is written in the inner part memory. A system is provided with a function where a data part except the ECC part is simultaneously transferred to a main storing device 500 so that data stored in the inner part memory 40 is corrected and transferred to the main storing device 500 after the termination of reading from the magnetic disk device 200. Thus, waiting rotation due to the correction processing is not generated so that there is an effect that a read operation is shortened even if lots of ECC read errors occur.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk control unit used in an information processing apparatus.

[0002]

2. Description of the Related Art Conventionally, in a magnetic disk controller, E
As a process of the magnetic disk control unit for the CC correctable error, the ECC correction internal memory has one sector, and the ECC correction is performed for each sector.

[0003]

According to the above-described conventional method for processing the ECC correctable read error of the magnetic disk controller, the ECC is corrected during a series of data transfer.
There is a drawback that overrun of the magnetic disk device occurs during ECC correction, rotation wait occurs, and the end of the read operation is significantly delayed.

[0004]

A magnetic disk control unit of the present invention is an EC for one transfer request sector from a host device.
An internal memory for holding read data with a C (error correction code) portion; a unit for writing the read data with an ECC portion read from the magnetic disk device to the internal memory; and a unit for writing the read data with an ECC portion to the internal memory. At the same time, a means for transferring the data part excluding the ECC part to the main storage device, and an ECC check while reading the read data with ECC from the magnetic disk device,
A means for storing a plurality of sector information in which the ECC error has occurred when a CC error occurs, and an ECC on the internal memory corresponding to the ECC error occurrence sector information stored in the storage means after the magnetic disk device finishes reading. A means for checking whether or not the error can be corrected, and if it can be corrected by the checking means, an EC
It is provided with means for generating a C correction code and correcting the data portion of the internal memory, and means for transferring the corrected data portion to the main storage device.

[0005]

The present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. In FIG. 1, a magnetic disk control unit 10
0 is a bus control circuit 10 and a microprocessor circuit 2
0, magnetic disk control circuit 30, internal memory 40, EC
C read data check circuit 50, RAM 60, and E
It is composed of a CC correction code generation circuit 70.

The magnetic disk control unit 100 is connected to the magnetic disk device 200, and is also connected to the central processing unit 400 and the main storage device 500 via the bus 300.

The operation of the magnetic disk controller 100 thus constructed is as follows. A read command from the central processing unit 400 to the magnetic disk unit 200 is sent to the bus 3
If it is input to the magnetic disk control unit 100 via 00, the microprocessor circuit 20 causes the magnetic disk device 200 to execute a seek operation via the magnetic disk control circuit 30.

When the microprocessor circuit 20 recognizes the completion of the seek operation via the magnetic disk control circuit 30, the microprocessor circuit 20 instructs the magnetic disk control circuit 30 to perform a read operation. When the magnetic disk control circuit 30 detects a target sector from the magnetic disk device 200, it reads the ECC section-attached data and writes it in the internal memory 40, and the data section excluding the ECC section is transferred via the bus control circuit 10 and the bus 300. Main memory 5
Write to 00. Further, the ECC read data check circuit 50 fetches the data with ECC and checks the ECC.

The microprocessor circuit 20 checks the ECC read data check circuit 50 every time the read operation of one sector is completed, and if an ECC error is detected, writes the sector value into the RAM 60.

Further, when the number of read sectors is checked through the magnetic disk control circuit 30 and the end of the read operation is recognized, the contents of the RAM 60 are checked to confirm the existence of an ECC error during the read operation so far. .. If no ECC error exists, a read operation end interrupt is issued to the bus control circuit 10 and the bus 300.
To the central processing unit 400, and the read operation is completed. If there is an ECC error, RAM
Internal memory 4 corresponding to the sector information written in 60
The data section and the ECC section of 0 are checked, and if correctable, the ECC correction code generation circuit 70
A correction code is generated, the data section is corrected, and the corrected data section is transferred to the main storage device 500 via the bus 300. When the processing of all the sector information written in the RAM 60 is completed, the microprocessor circuit 20 outputs an end interrupt to the central processing unit 400 via the bus control circuit 10 and the bus 300 to end the read operation.

If an uncorrectable ECC error is detected, the processing is stopped as a read error, and the microprocessor circuit 20 issues an end interrupt to the bus control circuit 10,
The data is output to the central processing unit 400 via the bus 300 and the read operation is completed.

[0013]

As described above, by adopting the magnetic disk control unit of the present invention, even if a correctable ECC read error occurs frequently, the rotation waiting due to the correction processing does not occur and the read operation is performed. The effect is that the execution time can be shortened.

[Brief description of drawings]

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

[Explanation of symbols]

 10 bus control circuit 20 microprocessor circuit 30 magnetic disk control circuit 40 internal memory 50 ECC read error check circuit 60 RAM 70 ECC correction code generation circuit 100 magnetic disk control unit 200 magnetic disk device 300 bus 400 central processing unit 500 main storage device

Claims (1)

Claim: What is claimed is: 1. An internal memory for holding read data with an ECC (error correction code) portion for one transfer request sector from a host device; and an ECC portion read read from a magnetic disk device. A unit for writing data to the internal memory; a unit for writing the read data with an ECC unit to the internal memory and simultaneously transferring a data unit excluding the ECC unit to a main storage device; and a read unit with an ECC from the magnetic disk device. A means for checking the ECC while reading the data and storing a plurality of sector information in which the ECC error has occurred when an ECC error occurs; and an ECC error stored in the storage means after the magnetic disk device finishes reading. Check whether ECC error in internal memory corresponding to the generated sector information can be corrected And a means for generating an ECC correction code to correct the data portion of the internal memory and a means for transferring the corrected data portion to the main storage device, if the correction is possible by the checking means. A magnetic disk control unit characterized by the above.