JPS58223860A - Magnetic disk controller - Google Patents

Abstract

PURPOSE:To reduce the effect of a CPU to the control time and to prevent deterioration of the control processing capacity of an information processor, by performing a verifying operation in the idle processing time of a magnetic disk device under the control of a magnetic disk controller. CONSTITUTION:An idle time control circuit 9 monitors the time interval during which an instruction is transmitted to a magnetic disk controller from a CPU. The idle processing time is decided when an interval longer than a fixed time is detected, and a verifying operation is indicated to a sequence control circuit 1. Then the verifying operation is controlled while reading successively the contents of a verifying control circuit 7 and an index register 8. Thus the verifying operation is carried out while an error is detected by a redundant bit control circuit 4. The contents of the register 8 are successively reset when a verifying operation is over. The verifying operation completes when the contents of the register 8 are all reset.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic disk control device, and more particularly to a magnetic disk control device for a hard disk device and a floppy disk device used in an information processing device such as an electronic computer.

Conventionally, in this type of magnetic disk drive, there is no appropriate detection method for detecting errors in write operations because there is only one head, so errors are detected by performing a read operation (usually called a verify operation) using software after the write operation. I am doing it.

As shown in FIG. 1, in a conventional magnetic disk control device, a sequence control circuit 1 controls the transmission and reception of signals in each operating mode, and an index register 2 stores signals in each operating mode and records the operating status of the magnetic disk device. is stored, and the result is reported to a central processing unit (hereinafter referred to as CPU) under the control of this sequence control circuit 10. The data conversion circuit converts data depending on the recording format, and the redundant bit control circuit 4 generates redundant bits (including parity, CRC, etc.) during write operations, and compares redundant bits during read operations. . The CPU interface control circuit 5 controls the interface signals between the CPU and the magnetic disk controller, and the magnetic disk interface control circuit 6 controls the interface signals between the magnetic disk controller and the magnetic disk device. By the way, in this magnetic disk control device, during a read operation, the redundant bit control circuit 4 performs error detection, but during a write operation, the redundant bit control circuit 4 generates redundant bits, so error detection cannot be performed, and the above-mentioned software Error detection is performed using this method. Therefore, this method has the disadvantage that it requires a lot of CPU control time, and if processing is attempted in real time, the control processing capacity of the information processing apparatus is reduced.

The present invention solves the above drawback by performing the verify operation during the raw processing time of the magnetic disk device under the control of the magnetic disk control device, and makes two rewrite operation control requests to the CPU at the time of a verify error. The present invention provides a magnetic disk control device.

According to the present invention, a magnetic disk control device in an information processing device has a register that stores a write control signal from a central processing unit, and the register stores the write control signal, and the central processing unit detects the presence or absence of an operation instruction command from the controller, and executes a verify operation of the data written to the magnetic disk device using the write control signal stored in the register during the raw processing time, and detects an error in the data. A magnetic disk control device is obtained, which is characterized in that it controls the central processing unit to send a control signal for rewriting when the central processing unit does so.

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 shows the basic blocks of a magnetic disk control device according to an embodiment of the present invention. In FIG. 2, the same parts as in FIG. 1 are designated by the same reference numerals, and explanations of the same parts will be omitted to avoid duplication.

The verify control circuit 7 is a control circuit for performing a verify operation during the raw processing time of the magnetic disk device, and has the same function as a read operation command from the CPU. The index register 8 stores a write control signal from the CPU when a write operation is performed as a verify control signal. The idle time control circuit 9 is a circuit that monitors the idle face signals of the CPU and the magnetic disk control device. When the sequence control circuit 1 receives a write command generated from the CPU through the CPU interface control circuit 5, it controls the write command so that the write command is sequentially stored in the index register. However, this index register 8 is designed not to store information other than write commands. The idle time control circuit 9 is a CPU
The time interval at which commands are transmitted from the magnetic disk controller to the magnetic disk controller is monitored, and when an interval longer than a certain level is detected, it is regarded as the raw processing time, and the sequence control circuit 1 is instructed to perform a peripheral operation, and together with the verify control circuit 7, the contents of the index register 8 are read. The verify operation is controlled while sequentially reading, and the verify operation is performed while the redundant bit control circuit 4 performs Scherrer detection.

On the other hand, when one verify operation is completed, the index register 8
The contents will be reset one by one. At this time, when the contents of the finger mark register 8 are all reset, the verify operation is completed. Therefore, when an error is detected by the redundant bit control circuit 4 during the verify operation, the sequence control circuit 1 transmits the CP through the CPU interface control circuit 5t.
It issues an alarm signal to U and sends the verify control signal of index register (2) 8 to the CPU as a rewrite control signal. If the sequence control circuit 1 issues a command from the CPU to the magnetic disk control device during the verify operation, the idle time control circuit 9 outputs a signal indicating that the operation is being executed and does not accept the command until the verify operation that is currently being executed is completed. In addition, it has a signal indicating the presence or absence of a verify control signal, which can be sent to the CPU upon request from the CPU, and can be used as a prevention signal when replacing the storage medium or turning off the power.

The present invention (d) As explained above, by providing a verify operation control circuit, etc., error detection after a write operation is performed during the raw processing time of the magnetic disk device, and the influence on the control time of the CPU is reduced, thereby reducing the impact on the information processing device. Control capabilities can be performed almost in real time.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a basic circuit of a conventional magnetic disk control device, and FIG. 2 is a block diagram showing a magnetic disk control device according to an embodiment of the present invention. 1... Sequence control circuit, 2... Index register, 3... Data conversion circuit, 4...
... Redundant bit control ML 5 ... CPU interface control circuit, 6 ... Magnetic disk interface control circuit, 7 ... Verification control circuit, 8 ... ...Indicator register, 9...
・Free time control circuit. In addition, the same reference numerals in the figures indicate the same parts and the corresponding parts.

Claims (1)

[Claims] In a magnetic disk control device in an information processing device,
It has a register that stores a write control signal from a central processing unit, stores the write control signal using the register, detects the presence or absence of an operation instruction command from the central processing unit, and executes the above-mentioned data during the idle processing time. A write control signal is used to verify the data written to the magnetic disk drive, and if an error is found in the data, a control signal is sent to the central processing unit for rewriting. A magnetic disk control device characterized by: