JPH03260745A - Duplex electronic disk device - Google Patents

Abstract

PURPOSE:To confirm the priority of the data on both primary and secondary electronic disk devices by providing an electronic disk processor which compares the contents stored in both disk devices with each other. CONSTITUTION:An electronic disk processor 200 detects the signal received from a timer 210 to select a primary electronic disk device 300 and reads out a fixed quantity of data to hold it. Then the processor 200 selects a secondary electronic disk device 400 and reads out a fixed quantity of data to compare this with the data read out of the device 300 and stored in the same memory address. If no coincidence is obtained between both data, the processor 200 reports this fact to a CPU via a line 001. Thus it is possible to confirm the coincidence between the data stored in both devices 300 and 400.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a duplex electronic disk device.

[Conventional technology]

Conventional redundant electronic disk drives perform normal error checking when executing instructions from the central processing unit.
The validity of data in the primary electronic disk device and secondary electronic disk device was guaranteed.

[Problem to be solved by the invention]

In the conventional redundant electronic disk device mentioned above, only a normal error check is performed when executing an instruction from the central processing unit, so depending on the nature of the failure, the contents stored in the primary electronic disk device and the secondary electronic disk device may be affected. The disadvantage is that it does not cause an error even if the numbers are different.

[Means to solve the problem]

The device of the present invention is a duplex electronic disk device that operates according to predetermined instructions from a central processing unit, and includes: a sub-system electronic disk device; a timer that outputs a signal at regular intervals; A certain amount of data is read from the primary electronic disk device and compared with the data stored at the same memory address in the secondary electronic disk device, and if the comparison results match, the next memory to be compared is The present invention is characterized by comprising an electronic disk processing device that creates addresses and, when the comparison results in a mismatch, reports the fact to the central processing unit.

〔Example〕

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

FIG. 1 is a block diagram showing an embodiment of the present invention, in which an electronic disk subsystem 100 includes an electronic disk processing device 200. Timer 210. Original electronic disk device 300
and a subsystem electronic disk 400.

The timer 210 sends a signal to the electronic disk processing device 200 through a line 201 at certain fixed time intervals. When the electronic disk processing device 200 detects the signal from the timer 210, it selects the primary electronic disk device 300, reads out a certain amount of data from addresses starting from memory address 0, and holds it in the electronic disk processing device 200.

Next, the electronic disk processing device 200 selects the secondary electronic disk device 400 through the line 401, reads a certain amount of data from addresses starting from memory address 0, and compares it with the data read from the primary electronic disk device 300. .

When the comparison results in a match, the electronic disk processing device 200 retains the address next to the last data read from the primary electronic disk device 300 in the memory within the electronic disk processing device 200 as a memory address for performing the next comparison operation. The next time a signal from timer 210 is detected, this memory address is used and the above operation is repeated.

When the comparison does not match, the electronic disk processing device 200 reports to the central processing unit that the comparison does not match through the line 001, and from now on, the command to this electronic disk device is reported as abnormal.

〔Effect of the invention〕

As explained above, the present invention provides a primary electronic disk device,
When duplicating files using a secondary electronic disk device, it is possible to confirm that the data stored in the primary electronic disk device matches the data stored in the secondary electronic disk device. effective.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention. 100...Electronic disk subsystem, 200
...Electronic disk processing device, 210...
・Timer, 300... Original electronic disk device,
400... Subsystem electronic disk device. 001,'107. Yo1. Gradient 1: Essence

Claims (1)

[Scope of Claims] A duplex electronic disk device that operates according to predetermined instructions from a central processing unit includes: a primary electronic disk device and a secondary electronic disk device that store data; and a timer that outputs a signal at regular intervals. , Each time the signal is detected, a certain amount of data is read from the primary electronic disk device and compared with data stored in the same memory address of the secondary electronic disk device, and if the comparison results match. A duplex electronic disk device comprising: an electronic disk processing device which creates a memory address to be compared next when the comparison is made, and reports the fact to the central processing unit when the comparison results in a mismatch.