JPH06131207A - Fault control method for input/output device - Google Patents

Abstract

PURPOSE:To effectively utilize a system resource by forming the input/output function of the input/output device into modules in specific units, and closing the function module corresponding to a fault and stopping the function if the fault occurs to the input/output device. CONSTITUTION:A control program is stored in a RAM 400 of a host device 100 and executed by a CPU 300 in sequence. A fault module deciding means 600 in the input/output device 200, on the other hand, detects a fault of a module; if the fault is detected, a fault module closing means 700 closes the faulty module and a closed module informing means 500 informs the host device 100 of fault information regarding the faulty module. The fault information reported to the host device 100 is registered in a command table set in the RAM 400. Consequently, it can immediately be decided whether a command is effective or ineffective, and the input/output device 200 can be used successively while part of its function is limited.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a failure control method when a part of the functions of an input / output device fails in a data processing system such as an electronic computer.

[0002]

2. Description of the Related Art In a data processing system such as an electronic computer, a command issued from a higher-level device such as a central processing unit is transferred to an input / output device such as a magnetic tape unit, and a process corresponding to the command, for example, data After the writing and reading are executed, the execution result is returned to the higher-level device, whereby a series of processing related to one command is completed.

FIG. 5 shows a flowchart of control operation in such a conventional data processing system. FIG. 7A shows the operation of a host device such as a central processing unit, and FIG. 7B shows the operation of an input / output device as a lower device.

First, the operation of the host device will be described with reference to FIG. When the host device is powered on, the RO
A boot program and the like in M are started up, and based on the boot program, initial settings such as checking the states of various components and reading a basic program into the main memory are performed (step S10).

When the initial setting is completed, the state of accepting a command is ready, and in step S10, a command from the user is awaited. When a command is input by the user, the process proceeds to the next step S12, and the input command is analyzed. If the issued command is found to be appropriate by the command analysis in step S12, the next step S1
In step 3, the command is transferred to an input / output device such as a magnetic tape device. Then, in the next step S14, the execution result wait state is entered until the command is executed by the input / output device and the execution result is returned.

Next, the operation of the input / output device will be described with reference to FIG. When the power of the input / output device is turned on, it is initialized in step S20, and waits for a command from the host device in step S21, like the above-described host device. If the command is transferred from the host device,
In step S22, the process corresponding to the command is executed, and after the process is completed, the execution result is sent back to the host device in step S23. Then, the process returns to step S21 to prepare for the next process.

On the host device side, when the execution result is returned from the input / output device, the result is received in step S14 of FIG. 5 (A), the process proceeds to the next step S15, and the execution result message is output to the CRT or the like. After that, the process returns to step S11 and waits for the input of the next new command.

[0008]

By the way, in the conventional data processing system, when a failure occurs in the input / output device, the error information is sent to the host device, and the input / output device in which the failure has occurred is , It was common to switch so that it cannot be used at all until the failure is recovered.

However, the input / output device in the data processing device has a plurality of processing functions such as a data writing process, a reading process, and an erasing process, depending on the device, for example, in the case of a magnetic tape device. Is normal. For this reason, in the case where a failure occurs in a part of the functions of the I / O device, it is impossible to make the I / O device unusable at all until the failure is recovered although other functions are normal. It is not preferable from the viewpoint of effective use of system resources.

The present invention has been made based on the above circumstances, and when an input / output device fails, only the failed function is blocked and disabled so that the system resources are effectively used. An object is to provide a failure control method for an output control device.

[0011]

In order to achieve the above object, a failure control method for an input / output device according to the present invention comprises a host device such as a central processing unit and an input device such as a magnetic tape device accessed by the host device. In a data processing system including an output device, the input / output function of the input / output device is modularized in a predetermined unit, and when a failure occurs in the input / output device, only the functional module corresponding to the failure is blocked and functions. The operation is continued while the functions of the input / output device are partially stopped.

[0012]

In the failure control method of the present invention configured as described above, when a command is issued from the user through the host device, if a part of the function corresponding to the command is issued in the input / output device. When there is a failure, only the module corresponding to the failed function is blocked and only that function is stopped. Therefore, after that, the processing for the faulty command cannot be accepted, but the corresponding processing can be executed for other commands. For this reason, it becomes possible to continue to use while limiting some of the functions.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an embodiment of a data processing system configured by applying the method of the present invention. In the figure, a host device 100 is a central processing unit (CPU) 30.
0, RAM 400 and the like. On the other hand, the input / output device 200, which is a lower-level device, has the blocking module notification means 5
00, a failure module determination means 600, a failure module blocking means 700, and a module group in which various functions of the input / output device are divided into predetermined units.

A control program corresponding to the procedure shown in FIG. 2A, which will be described later, is stored in the RAM 400 of the host device 100, and the CPU 300 sequentially executes the control program.
On the other hand, the faulty module determination means 6 in the input / output device 200
Reference numeral 00 indicates a failure of the module. When a failure is detected, the failure module closing means 700 closes the failure module, and the closed module notifying means 500 sends the failure module to the higher-level device 100. Failure information is notified. The failure information notified to the host device 100 is registered in the command table set in the RAM 400.

FIG. 2 is a flow chart of the control operation of the above embodiment. FIG. 2A shows the operation of the host device 100.
FIG. 2B shows the operation of the input / output device 200 as a lower device. The operation of the above embodiment will be described in detail below with reference to the flowchart of FIG.

When the system is operated, the host device 100
Waits in a command waiting state in step S100 of FIG. When there is a command input from the user, the CPU
300 analyzes the command in step S101, and if the command is appropriate, proceeds to step S102 and refers to the command table.

As a result of referring to the command table, when it is determined in step S103 that the issued command is normal and the command can be completely executed, the process branches to step S104 to transfer the command to the input / output device 200. To do.

On the other hand, as a result of referring to the command table,
If the failure information is registered for the command and it is determined that the command cannot be executed with the original perfect function, the process proceeds to step S105, and whether the command can be executed with its function partially limited. It is determined whether or not.

If the command can be executed with a limited part of its function, the process branches to step S106 and is transferred to the input / output device 200 as a limited command. If it is determined that the command cannot be executed even if the function of the command is limited, the process branches to step S107 to output an invalid message for the issued command.
After notifying the user by displaying it on the RT or the like, the process returns to step S101 again to repeat the above process.

When the host device 100 transfers the command or the limited command to the input / output device 200 in steps S104 and S106, it waits for the processing result of the command execution from the input / output device 200 (step S).
108).

The input / output device 200 waits for the arrival of a command from the host device 100 in step S200 of FIG. 2 (B). When the command is transferred from the higher-level device 100, in step S201, the failure module determination unit 600 checks the failure of each module used to execute the command, and determines whether each function is normal or not in module units. Will be verified in.

If no failure is detected in any of the modules, the process proceeds to step S203 and the process corresponding to the command is executed. Then, step S20
In 4, the execution result is transferred to the host device, and then the process returns to step S200 to wait for the next command.

On the other hand, if a failure is detected in the module, failure information is created in step S205, and then the failure module closing means 700 executes the closing processing of the failure module in step S206. Then, in step S207, the failure information is reported to the higher-level device 100 through the blocking module notification means 500, and then the process returns to step S200 and waits for the next command.

In step S108 of FIG. 2A, the higher-level device 100 waits in a state of waiting for the execution process result from the input / output device 200. Therefore, the input / output device 2
When the processing result report is received from step 00 in step S204 or step S207 of FIG. 2B, the process proceeds to step S109, and it is determined whether the report is a normal processing result report or a failure information report.

If it is the report of the normal processing result, the process proceeds to step S110, a message regarding the execution result is output, and the series of processing is ended. On the other hand, if the report is failure information, the process proceeds to step S111, and necessary failure information such as the module number in which the failure has occurred and the command name corresponding to the failed module is registered in the command table prepared in the RAM 44. . And step S
At 112, a predetermined invalid message is output to end the series of processes for the command, and the process returns to step S100 to wait for the next command.

As described above, when the failure information for the input command is registered in the command table, the command table in the RAM 400 is referred to from the next time (step S102) to enable / disable the command. Can be determined immediately (step S
103, S105).

Therefore, after the failure information is once registered in the command table, even if a command for the functional module in which the failure has occurred is input, the command is treated as invalid, and thus the input / output device 200.
Can be used continuously with some of its functions limited.

FIG. 3 shows a concrete example of the faulty module blocking means 700 in FIG. The fault module blocking means of FIG. 3 is configured to directly block the fault module in terms of hardware, and includes an error code addition circuit 710, an error code decoder 720, and a fault module blocking AND gate 730. There is.

When a failure occurs in the functional module in the input / output device, it is detected by the failure module determination means 600 in FIG. 1, and a module failure signal is sent to the error code addition circuit 710. The error code adding circuit 7 creates predetermined failure information by coding the number of the failed module and the details of the failure by a predetermined method and adding the code to the error data.

The decoder 720 decodes this failure information, and gives a blocking signal to one input terminal of the AND gate 730 of the module in failure. In this state, the AND gate 703 is operated from the CPU (not shown) in the input / output device.
When an operation signal (ENABLE signal) for the module is applied to the other input terminal of the module, a module blocking signal is output from the AND gate and the corresponding module is blocked by hardware. At the same time, the CPU in the input / output device reports the failure information created by the error code adding circuit 710 to the higher-level device 100 through the blocking module notification means 500 in FIG.

FIG. 4 shows the fault module closing means 70.
Another example of 0 is shown. The failure module blocking means in FIG. 4 is configured to block the failure module by jumping the processing routine of the function module in which the failure has occurred, when each function module is configured in a firmware manner. , Error code addition circuit 51
0, a multiplexer (MPX) 520, and a plurality of AND gates 530 corresponding to each module.

An error code for the corresponding module is given from the error code adding circuit 510 to one input terminal of each AND gate 703. On the other hand, the multiplexer 520 sequentially outputs the function confirmation signal to the other input terminal of each AND gate 730, and sequentially opens the gate of each AND gate. Therefore, if the error code is input from the error code adding circuit 510 to the AND gate at the position where the gate is opened, the error code is input through the AND gate to the CPU (not shown) in the input / output device.
Will be notified to.

Upon receiving the error code, the CPU in the input / output device jumps to the processing routine of the faulty module designated by the error code.
The faulty module is blocked by software. At the same time, the CPU in the input / output device displays the failure information created by the error code adding circuit 710 in FIG.
Upper device 1 through the blocking module notification means 500 in the
Report to 00.

[0034]

As described above, according to the failure control method of the present invention, when a failure occurs in a part of the functions of the input / output device, only the functional module in which the failure occurs is blocked, and the input / output is terminated. Since some of the functions of the device can be continuously used while being limited, it is possible to effectively use the resources in this type of data processing system.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a data processing system configured by applying a method of the present invention.

FIG. 2 is a flowchart of the control operation of the above embodiment.

FIG. 3 is a block diagram showing a specific example of faulty module closing means in the embodiment.

FIG. 4 is a block diagram showing another example of the faulty module closing means.

FIG. 5 is a flowchart of the control operation of the input / output device according to the conventional method.

[Explanation of symbols]

 100 Upper device 200 Input / output device 300 Central processing unit (CPU) 400 RAM 500 Blocking module notification means 510 Error code addition circuit 520 Multiplexer (MPX) 530 AND gate 600 Fault module determination means 700 Fault module blocking means 710 Error code addition circuit 720 Decoder 730 AND gate

Claims (1)

[Claims] 1. A data processing system comprising a host device such as a central processing unit and an input / output device such as a magnetic tape device accessed by the host device, wherein the input / output function of the input / output device is a predetermined unit. When a failure occurs in the input / output device, only the function module corresponding to the failure is blocked and stopped, and the operation is continued while partially limiting the function of the input / output device. Characteristic I / O device failure control method.