JPS5952861B2 - Transfer device switching method for asynchronous processing system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic switching system including two electronic switching processing devices (hereinafter referred to as processing devices).

As this type of electronic exchange system, a system has been proposed in which two processing devices operate asynchronously and data is exchanged between the processing devices via a transfer device. In this system, in addition to the transfer device in use, a backup transfer device is provided, and if a failure occurs in the transfer device in use, a system is adopted in which the transfer device is switched to the backup transfer device. When switching transfer devices, since the two processing devices operate asynchronously, one of the processing devices detects a failure in the transfer device, and
When a transfer device is switched, it is necessary to notify the other processing device that the transfer device has been switched. For this reason, normally, a maintenance device is provided to monitor the status of the two transfer devices, and each processing device issues a switching command to the maintenance device to switch between the faulty transfer device and the backup transfer device. . However, this method has disadvantages in terms of economy because it requires a maintenance device in addition to the current and backup transfer devices. Furthermore, when a failure occurs in the maintenance device, there is a drawback that the backup transfer device is not switched to even though the backup transfer device is normal. An object of the present invention is to provide an asynchronous processing type transfer device switching system that does not require a maintenance device.

Another object of the present invention is to provide a transfer device used in an asynchronous processing system that has a function of detecting transfer device switching and transmitting the information to two processing devices.

According to the present invention, in a transfer device that controls data transfer between two processing devices that are operated asynchronously, a switching signal that is set upon receiving a transfer device switching request from one of the processing devices is sent, and both processing devices A switching request display circuit that stops the switching signal upon receiving a reset request indicating that the switching of the transfer device in the device has been completed; In contrast, a transfer device is obtained which has a state reading circuit configured to be able to send a switching signal in the transfer device and other transfer devices.

Furthermore, the present invention has two electronic exchange processing devices that operate asynchronously and two transfer devices that control data transfer between the two processing devices, and when a failure occurs in one of the transfer devices, In this case, in an asynchronous processing type transfer device switching method configured to switch to another transfer device, the processing device has a function of periodically sending a status read command to the transfer device to read the status of the transfer station; It has a function of sending a switching request set command for instructing switching of the transfer device and a switching request set command for canceling this set command, and each transfer device receives the set command and set command sent from the processing device. An instruction storage circuit that stores various instructions including instructions, an instruction decoder circuit that decodes the instructions, and a switching request display circuit that can be set or reset from either side of both processing devices by switching request set and reset commands. An asynchronous processing type transfer device switching method is provided which includes a reading circuit that can simultaneously read the output of a switching request display circuit compatible with both transfer devices from either processing device in response to a periodically issued status reading command. It will be done.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

Referring to FIG. 1, the electronic exchange system according to the present invention includes first and second electronic exchange processing devices 1 that are operated asynchronously.
and 2, and two transfer devices 3 connected between both processing devices.
, 4.

Of these, only one of the two transfer devices 3 and 4 is used.
The other is on standby as a backup device. Hereinafter, the transfer device 3 will be described as a used device and the transfer device 4 as a standby device. 1st
The second processing devices 1 and 2 have a function of sending a read command to the transfer device 3 or 4 at predetermined intervals, a function of identifying a transfer device in use, and a function of identifying a transfer device in use and a failure of the transfer device in use. It shall be equipped with a function to detect. Further, each processing device 1, 2 supplies a switching request set command to the backup device 4, instructing to set a switching request for the transfer device when a failure occurs in the device 3 used,
When the other processing device detects that the transfer device has been switched, it sends a switching request set command to the backup device 4 to cancel the switching request set command to the backup device 4. Note that detection of switching of the transfer device in the other processing device is performed by a read command periodically sent from each processing device. Referring to FIG. 2, the internal configurations of the two transfer devices 3 and 4 are shown.

Here, to explain the transfer device 3 as an example, the instruction storage circuits 5 and 6 that accumulate various instructions sent from the first and second processing devices 1 and 2 shown in FIG. Instruction decoder circuits 7 and 8 for decoding are provided. Instruction decoder circuits 7 and 8 are connected to processing units 1 and 2.
In addition to normal commands from , it has the function of decoding switching request set commands and switching request set commands. When the switching request set command is decoded in the instruction decoder circuits 7 and 8, the decoded outputs are sent to the set terminals 9 and 10, respectively.On the other hand, when the switching request noset command is decoded, the decoded outputs are sent to the set terminals 9 and 10, respectively. It is sent out to terminals 11 and 12. Also,
When the periodically applied status read command is decoded by each command decode circuit 7, 8, the output thereof is sent to gate terminals 15, 16, respectively. Furthermore, this embodiment has a switching request flip-flop circuit 13 to indicate whether switching of the transfer device 3 is required, and this flip-flop circuit 13 outputs an OR gate from set terminals 9 and 10. It is set by the decode output applied through the reset terminal 1 and sends an output signal to the output terminal 14, and is reset by the decode output applied from the reset terminals 1], 2 through the OR gate.

The output of the flip-flop circuit 13 is transmitted through the output terminal 14 to the transfer device 3 composed of a plurality of AND gates.
It is sent to the reading circuit of the other transfer device 4 and also sent to the reading circuit of the other transfer device 4 having a similar configuration. The reading circuit includes a flip-flop circuit in the transfer device 3] in addition to a pair of AND gates for transmitting the state of the flip-flop circuit 3.
A pair of AND gates is provided for sending out the state of another transfer device 4, and each pair of AND gates is connected to the first and second processing device 1.
and 2, respectively. Among these, the two AND gates on the first processing device 1 side transfer the displayed states of both transfer devices 3 and 4 to the first processing device 1 when the state read command is decoded in the instruction decoder circuit 7. do. On the other hand,
The two AND gates facing the second processing device 2 transfer the states of the transfer devices 3 and 4 to the second processing device 2 when the state read command is decoded by the instruction decoder circuit 8. Note that the transfer device 4 has the same configuration as the transfer device 3, and corresponding parts are given the same reference numerals. below,
The operation will be explained with reference to FIG.

Here, as in FIG. 1, it is assumed that the transfer device 3 is in use and the transfer device 4 is in a standby state, and a failure of the transfer device 3 that is in use is detected in the first processing device 1. I will explain about it. The first processing device 1 that has detected the failure first sends a switching request set command to the transfer device 4 on standby. This set command is decoded by the command decoder circuit 7 of the transfer device 4, and then sent to the set terminal 9.
The signal is applied to the switching request flip-flop circuit 13 in the transfer device 4 to set it. This state is given to the reading circuit within the transfer device 4 through the output terminal 14, and is also supplied to the reading circuits of other transfer devices 3. The second processing device 2 simultaneously reads the outputs of the output terminals 14 of the switching request flip-flop circuits 13 of both transfer devices 3 and 4 via the transfer device 3 in response to a status read command which is a periodic command.

As a result, it is detected that the switching request display is displayed on the transfer device 4 that is on standby as a standby device, and while the transfer device 3 currently in use is on standby, the transfer device 4 that is on standby is in use. You can start operation by switching to Transfer while the second processing device 2 is waiting. When using the device 4, a switching request set command is sent to the transfer device 4 to reset the switching request flip-flop circuit 13 in the transfer device 4. The first processing device 1 that has detected the fault detects that the switching request flip-flop circuit 13 of the standby transfer device 4, which was set at the time of the fault detection, has been reset, using a status read command issued periodically. . Thereby, the first processing device 1 can detect that the switching of the second processing device 2 to the transfer device 4 has been completed. In the embodiment described above, each transfer device is provided with a reading circuit so that the switching request status of other transfer devices can also be read.

Therefore, for example, when the switching request flip-flop circuit 13 of the transfer device 4 is set by a switching request set command from the first processing device, the second processing device 2 periodically reads the status of only the transfer device 3. Even if a command is given, it is possible to detect that a switching request set command is issued to the transfer device 4. In this way, both the flip-flop circuits 13 of the transfer devices 3 and 4 shown in FIG. 2 are reset in the normal state, and are set only during the period from the switching request to the end of switching between the two processing devices. I know that there is. According to the present invention, as described above, a switching request display circuit is provided for each transfer device, and a reader configured to read the status of two switching request display circuits corresponding to the transfer device from both electronic exchange processing devices. circuit, thereby making it possible to perform two
You can switch between two transfer devices.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a schematic configuration of a system according to the present invention, and FIG. 2 is a circuit diagram showing a transfer device according to an embodiment of the present invention. Explanation of symbols, 1, 2: electronic exchange processing device, 3, 4: transfer device, 5, 6: instruction storage circuit, 7, 8: instruction decoder circuit, 9, 10: set terminal, 11, 12: reset terminal, 13: switching request flip-flop circuit, 14: output terminal, 15, 16: reading circuit gate terminal.

Claims (1)

[Claims] 1. First and second electronic exchange processing devices that are operated asynchronously, and a plurality of units that are provided between the first and second electronic exchange processing devices and that control the transfer of information between both electronic exchange processing devices. a transfer device, each of the transfer devices is set upon receiving a switching request from both the electronic exchange processing devices,
A first circuit that sends a switching signal and stops the switching signal upon receiving a reset request from both electronic exchange processing devices indicating that the switching of the transfer device is completed, and a first circuit that transmits the switching signal of the transfer device and other transfer devices. and a second circuit for transmitting signals to both of the electronic exchange processing devices, and when a failure occurs in one of the transfer devices, the transmission from the failed transfer device to the other transfer device is provided. An asynchronous processing type transfer device switching method characterized in that switching is performed using first and second circuits in each of the transfer devices.