JPH03172921A - Electronic disk system - Google Patents

Abstract

PURPOSE:To attain switching between single and double write modes by giving the same device address to two electronic disk devices when two electronic disk devices are set to the dual writing mode and giving individual device addresses to both devices when two electronic disk devices are set to the single writing mode. CONSTITUTION:Electronic disk devices 2 and 3 are connected to an electronic disk controller 1 through a common electronic disk interface 4, and devices 2 and 3 are provided with single and dual writing mode control registers 25 and 35 and device address comparators 24 and 34. When the operation to operate devices 2 and 3 in the double write mode for the write of the same contents is instructed by the controller 1, registers 25 and 35 give the same device address to devices 2 and 3 to operate them in the double write mode. When the operation to operate them in the single write mode for write of individual contents is instructed, individual device addresses different from the same device address are allowed to operate them in the single writing mode.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention is applied to an electronic disk system. The present invention relates to an electronic disk system that can perform maintenance and confirmation work by switching to a single-write operation mode while operating in a dual-write operation mode.

〔overview〕

The present invention provides an electronic disk system in which an electronic disk control device controlled by a host device controls two electronic disk devices connected via a common interface, in which the two electronic disk devices change their device addresses. ,
-By being able to switch to either overwrite or double write operation mode, special operations can be performed when performing maintenance and confirmation work on either electronic disk device during system operation. This eliminates the need for

[Conventional technology]

Conventionally, this type of electronic disk system has not been able to switch two electronic disk devices into single write and double write operation modes.

[Problem that the invention seeks to solve]

Therefore, in the conventional electronic disk system, when maintenance work is performed on one side of the electronic disk device in a dual-write configuration during operation, there is a drawback that execution of a test program from the host device cannot be confirmed.

The present invention solves this problem by switching to either overwrite or double write operation mode, and allows maintenance and confirmation work to be performed on one device even while the system is in operation. The purpose is to provide a system.

[Means for solving problems]

The present invention provides an electronic disk system comprising two electronic disk devices connected to a common interface and an electronic disk control device that controls the two electronic disk devices via this interface according to the control of a host device. , the electronic disk device includes:
When the two electronic disk devices are in a double write mode in which they write the same content, the same device address is given to the two electronic disk devices, and the two electronic disk devices write in a single write mode in which they write separate contents. In this case, the present invention is characterized by comprising means for giving individual device addresses different from the same device address to the two electronic disk devices.

Each electronic disk device is provided with a comparison circuit that compares the device address transmitted to the interface with the device address of the own device, and the means for providing the device address is configured to provide the device address to the comparison circuit according to the mode. It may include means for providing the addresses as different addresses.

[Effect]

When two electronic disk devices are in dual write mode in which they write the same content, the same device address is given to the two electronic disk devices, and either the two electronic disk devices write separate contents, or one electronic disk device writes the same content. When switching to single write mode to disconnect disk devices, the two electronic disk devices are given individual device addresses that are different from the same address.

As a result, even when the system is in operation, it is possible to switch to the single write mode and recognize one electronic disk device as a separate device from the electronic disk device in use, and perform maintenance and confirmation work.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

The figure is a block diagram showing the configuration of an embodiment of the present invention.

Embodiments of the present invention utilize a common electronic disk interface 4.
The two electronic disk devices 2 and 3 are connected via this electronic disk interface 4 under the control of a host device (not shown).
When the two electronic disk devices 2 and 3 are in the dual write mode in which they write the same content, the electronic disk devices 2 and 3 respectively have an electronic disk control device 1 that controls the electronic disk devices 2 and 3. When the same device address is given to the two electronic disk devices 2 and 3, and the two electronic disk devices 2 and 3 are in single write mode in which separate contents are written, the same device address is given to the two electronic disk devices 2 and 3. Single/double write mode control registers 25 and 35 that provide different individual device addresses, and device address comparison circuits 24 and 34 that compare the device address sent to the electronic disk interface 4 with the device address of its own device. The double/double write mode control registers 25 and 35 include means for supplying the address of the own device as a different address to the device address comparison circuits 24 and 34 according to the mode, and interface control circuits 23 and 33 that control the transmission and reception of information between the interface control circuits 23 and 33, storage circuits 21 and 31 that store data from these interface control circuits 23 and 33, and this section 1. It includes read/write control circuits 22 and 32 that control reading and writing of data to and from circuits 21 and 31.

Next, the operation of the embodiment of the present invention configured as described above will be explained.

In normal information transmission and reception, when data is sent from a higher-level device (not shown), the electronic disk control device 1 sends the data to the interface control circuit 23.33 of the electronic disk device 2.3 via the electronic disk interface 4. The interface control circuit 23.33 writes the received data into the storage circuit 21.31 under the control of the read/write control circuit 22.32.

In addition, when receiving an instruction to transmit data to a higher-level device (not shown), the interface control circuits 23 and 33 read and
The storage circuit 21 under the control of the write control circuit 22.32
．． 31, and the read data is transmitted to the electronic disk controller 1 via the electronic disk interface 4, and then transmitted to a higher-level device (not shown) under the control of the electronic disk controller 1.

Here, when an instruction to operate in a dual write mode in which the same content is written is issued from a higher-level device (not shown) via the electronic disk control device 1 and the electronic disk interface 4, the - double/dual write mode control register 25 is issued. .35 is an instruction to give the same device address to each of the two electronic disk devices 2.3 and operate in dual write mode, and to operate in single write mode in which the two electronic disk devices 2.3 write individual contents. When the
The double write mode control register 25.35 gives an individual device address different from the same device address, and operates in the -overwrite mode.

In addition, the double/double write mode control register 25.35 controls the device address comparison circuit 24.34 according to the designated mode.
, the address of the own device can be given as a different address, and this address -b, < the given device address comparison circuit 24.34 compares the transmitted device address with the given device address of the own device. However, if they match, the single write mode is operated, and if they do not match, the double write mode is operated.

During system operation in this way, for example, if an instruction is given from the host device to run a test program and perform confirmation work after maintenance work has been performed on the electronic disk device 2, then - The mode control register 25 switches the double write operation mode to the single write operation mode, sets the interface control circuit 23 to the single write operation mode, changes the device address held in the device address comparison circuit 24, and the electronic disk device 2 The test program can be executed so that it is recognized by the electronic disk control device 1 as a separate device from the electronic disk device 3.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to switch an electronic disk device with a dual writing configuration to either the single writing or dual writing operation mode, and to easily change the device address. This has the advantage that maintenance and confirmation work can be performed on one electronic disk device even while the system is in operation.

[Brief explanation of the drawing]

The figure is a block diagram showing the configuration of an embodiment of the present invention. 1... Electronic disk control device, 2.3... Electronic disk device, 4... Electronic disk interface, 21
．． 31...Storage circuit, 22.32...Read/write control circuit, 23.33...Interface control circuit, 24.34...Device address comparison circuit, 25.35
...-Double/double write mode control register.

Claims (1)

[Claims] 1. Two electronic disk devices connected to a common interface, and an electronic disk control device that controls the two electronic disk devices via this interface according to the control of a host device. In the electronic disk system, each of the electronic disk devices includes: when in a dual write mode in which the two electronic disk devices write the same content, the same device address is given to the two electronic disk devices; An electronic disk system characterized by comprising means for giving individual device addresses different from the same device address to the two electronic disk devices when the electronic disk devices are in a single write mode in which individual contents are written. . 2. The electronic disk system according to claim 1, wherein each electronic disk device is provided with a comparison circuit that compares the device address transmitted to the interface with the device address of the own device. 3. The electronic disk system according to claim 2, wherein the means for giving the device address includes means for giving the address of the own device as a different address to the comparison circuit depending on the mode.