JPH0469755A - Information processor - Google Patents

Abstract

PURPOSE:To execute an exact decision at the time when a fault occurs by detecting a fault of an input/output controller from information for showing its elapsed time, in the case an NAK response is executed by the input/output controller. CONSTITUTION:When an input/output controller 30 becomes a state of executing a negative acknowledge response (NAK response) executed at the time when an I/O instruction cannot be received due to an internal operation, a time counting part 32 is allowed to start a time counting operation. The time counting part 32 outputs the time counting contents to an arithmetic processor 10, and the arithmetic processor 10 receives the NAK response of the input/ output controller 30, and also, decides whether the input/output controller 30 is in the course of internal operation or in the course of hardware fault by comparing data for showing the time counting contents of the time counting part 32 with data given in advance to the inside of the arithmetic processor 10 by a comparing part 11. In such a way, whether the NAK response of the input/output controller 30 is executed due to an internal operation or occurrence of a fault can be decided exactly by the arithmetic processor 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an information processing device, and particularly to an information processing device in which an arithmetic processing unit detects a hardware failure in an input/output control device.

[Conventional technology]

In this type of information processing device according to the conventional technology, in an information processing device in which an arithmetic processing unit and an input/output control device are connected to a common bus, the input/output control device performs internal operation.
Hardware in which if an I/O (input/output) command issued by an arithmetic processing unit cannot be accepted for a certain period of time, the input/output control unit responds with a NAK to the arithmetic processing unit in response to the I/O command received during that period. He was taking measures.

[Problem to be solved by the invention]

The problem with this type of information processing device based on conventional technology is that the input/output control device has a hardware NA due to internal operations.
If a failure occurs in the input/output control device after a K response is issued, the NAK response will be issued forever, so on the arithmetic processing device side that issues the I/O command, the input/output control device will not be able to control internal operations. The problem is that it cannot be accurately determined whether the NAK response is being made because of a failure or because a failure has occurred.

An object of the present invention is to solve the problems caused by the above-mentioned prior art.
An object of the present invention is to enable an arithmetic processing device to accurately determine whether a NAK response from an input/output control device is due to an internal operation or a failure.

[Means to solve the problem]

The information processing device of the present invention has an arithmetic processing device and an input/output control device connected to a common bus, wherein the input/output control device receives an I/O command from the arithmetic processing device for internal operation. When a negative response (hereinafter referred to as a NAK response) is made when the input/output control device is unable to respond, the hardware timekeeping means that starts a timekeeping operation and the input/output control device are in a state of making a NAK response. and means for responding with information indicating the elapsed time since N A
The device is configured to include means for detecting a failure in the input/output control device from information indicating the elapsed time when a K response is made.

〔Example〕

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

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

When the input/output control device 30 enters a state in which it makes a NAK response due to an internal operation or a hardware failure, the input/output control section 33, which is the control section of the input/output control device 30, Timing unit 3 that measures elapsed time
2 to start the timing operation.

When the arithmetic processing unit/O that issues an I/O command issues an I/O command to the input/output control device 30, the transmitter/receiver 31 that performs transmission/reception with the common bus inside the input/output control device 30 The input/output control unit 30 is notified that the /O command has been received.

Since the input/output control section 30 is in the state of making a NAK response, it instructs the transmitter/receiver section 31 to output the NAK signal, and at the same time instructs the timer section 32 to output the time measurement contents to the arithmetic processing unit/O. The clock unit 32 converts the time measurement contents into 8-bit data and sends it to the arithmetic processing unit/O through an 8-bit signal line.
Output to.

Therefore, the arithmetic processing unit/O
In addition to accepting the AK response, it also receives 8-bit data representing the time measurement content of the timer 32, data given in advance to the inside of the arithmetic processing unit/O (data representing the maximum time required for internal operation of the input/output device 30). By comparing these in the comparison unit 11, it is determined whether the input/output control device 30 is in internal operation or is experiencing a hardware failure.

When the state of performing the NAK response is released, the input/output control section 33 resets the time measurement contents of the time measurement section 32.

〔Effect of the invention〕

As explained above, in the present invention, the input/output control device
When a NAK response is made to an instruction, the arithmetic processing device can accurately determine whether the problem is due to an internal operation or a hardware failure.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. /O... Arithmetic processing unit, 11... Comparison unit, 20...
- Common bus, 30... Input/output control device, 31... Transmission/reception section, 32... Time measurement section, 33... (Input/output) control section, 34... Internal bus, 35... Time measurement Data signal line (8 bit width).

Claims (1)

[Claims] In an information processing device in which an arithmetic processing unit and an input/output control device are connected to a common bus, a negative response (a (hereinafter referred to as NAK response)
The input/output control device has a hardware timer that starts a timekeeping operation when the input/output control device is in a state to perform a NAK response, and a means for responding with information indicating the elapsed time since the input/output control device became in a state to perform a NAK response. Information processing characterized in that the arithmetic processing unit includes means for detecting a failure of the input/output control device from information indicating the elapsed time when the input/output control device makes a NAK response. Device.