JPS5941210B2 - How to handle power failure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a processing method when a power failure occurs in a terminal control device in a system including a computer, a terminal control device, and a terminal device.

It consists of a computer (central processing unit), a terminal control device, and a terminal device.

For example, in a totalizer system that sells and tallies voting tickets, if the power to the terminal control device is cut off for some reason, this power cut can be recognized by a computer, but it is not possible to recognize that the power has been restored without human intervention. It couldn't be done automatically. Conventionally, a control device whose power has been temporarily cut off due to some kind of failure does not automatically attempt recovery, but is temporarily disconnected from the system and operated in fallback mode. However, in this fallback mode, if the system suffers a double failure or a series of failures occurs, the reliability and availability will drop significantly compared to when all systems are operating normally. However, it may be fatal to the operation of the system.
The purpose of the present invention is to solve the above-mentioned problems, and the control device in which a failure has occurred notifies power restoration, automatically attempts recovery processing, and reincorporates into the system, thereby automatically performing recovery processing. Mean recovery time
ToRepalr) This improves system reliability and operation rate as MTTR is shortened.

The object of the present invention is to provide an information processing system consisting of a large number of terminals, a terminal control device that controls the terminals, and a central processing unit. This is achieved by sending a power restoration message to the processing device, and the central processing device automatically performing recovery processing for the control device based on the received power restoration message.

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

FIG. 1 is a block diagram of a terminal control device according to an embodiment of the present invention, FIG. 2 is a time chart showing a processing sequence between the control device and a computer according to an embodiment of the present invention, and FIG. 3 is a processing flowchart.

In the figure, 1 is a computer, 2 is a control device, 3 is a terminal device, 4 is a transmission line, 5 is a CPU in the control device, 6 is a power failure detection circuit, 7 is a power recovery detection circuit, 8 is a ROM, 9 is a register,
10 indicates a message sending control circuit.

When the control device 2 is powered off due to some kind of failure, the power failure detection circuit 6 of the control device 2 operates and stores the cause of the failure and the status of the power failure in registers 9 (non-volatile).

After that, when the power is restored to the control device, the power restoration detection circuit γ operates to issue a high priority interrupt such as level "O" to the CPU 5.

The CPU 5 detects this interrupt and writes it to the built-in ROM.
Start the microprogram No. 8. Control device 2 is RO
By running the microprogram of M8, the computer 1 is notified of the status of the cause of the failure and a message indicating that the power has been restored through the message sending control circuit 10.

When the computer 1 receives the status of the cause of the failure and a message to the effect that the power has been restored from the control device 2, it responds to the control device 2 with a message to the effect that it has received this. The control device 2 continues to send the status of the cause of the failure and a message to the effect that the power has been restored to the computer 1 repeatedly at a certain period until a response is received from the computer 1 to the effect that the power has been restored.

The computer 1 analyzes the details of the failure received from the control device 2 and starts a program according to the details.

The computer instructs the control device 2 to perform recovery processing depending on the details of the failure.

As an example of this recovery process, the failure details (level of importance) of the control device
1 IPL (Initial, Program, Load) depending on
and start from the very beginning.

2.Restart in fallback mode with the part where the failure occurred isolated.

3. Diagnose the part where the failure occurred from the computer side.

4 Performs processing such as restarting from the state immediately before the power was cut off.

The above processing sequence and processing flowchart are
As shown in FIG.

As explained above, if the control device loses power due to some kind of failure and then returns, it is possible to automatically notify the computer side of a power recovery message from the control device, allowing the computer to recognize the power recovery. This is what I did.

As a result, the computer and control device automatically perform the process from power restoration notification to the computer to recovery processing of the computer and control device by exchanging messages, shortening the MTTR and improving the system. The reliability and operation rate of the system will be dramatically improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a control device according to an embodiment of the present invention;
FIG. 2 is a time chart showing a processing sequence between a control device and a computer according to an embodiment of the present invention, and FIG. 3 is a processing flow chart.

Claims (1)

[Scope of Claims] 1. In an information processing system consisting of a large number of terminals, a terminal control device that controls the terminals, and a central processing unit, when the control device has a power outage, its status is stored in a non-volatile storage means and the status is restored. When the power is restored, the control device sends a power recovery message including the status to the central processing unit, and the central processing unit analyzes the received power recovery message and automatically performs recovery processing for the control device. Features a processing method in the event of a power failure. 2. The processing method in the event of a power failure according to claim 1, characterized in that sending of a power recovery message is controlled by a microprogram in a ROM built into the control device. 3. Claim 1 or 2, characterized in that the power restoration message is repeatedly sent to the central processing unit at a predetermined timing until a response indicating that the power restoration message has been received by the central processing unit is sent to the control device. Processing method for power failure described in section.