JPS63146135A - Self-diagnostic system for circuit - Google Patents

Abstract

PURPOSE:To detect the abnormality of a circuit in its early state by providing a power supply part whose output voltage is varied with a control signal and self-diagnosing the circuit with the voltage changed from a fundamental voltage. CONSTITUTION:A power supply part 2 of a device 1 is so constituted that its output can be varied to the fundamental voltage and - or + alpha% fundamental voltage, and the initial test for power rise and the operation test for maintenance are performed with not only the fundamental voltage (for example, +5V) but also + or -alpha% fundamental voltage (for example, +5.25V and +4.75V). Thus, the test for the variation of power is performed in the user side also, and a circuit, a device, or the like which is ready to be faulty or is suspicious is detected in the early stage.

Description

[Detailed description of the invention] [Table of contents] Overview Industrial field of application Prior art (Figure 4) Problems to be solved by the invention Means for solving the problems (Figure 1) Working examples (Figure 1) (Figures 2 and 3) Effects of the Invention [Summary] The present invention is a circuit self-diagnosis system that is used to detect deterioration or defective products due to long-term use of circuit components of terminal devices, or to check whether they can withstand voltage fluctuations. For checking, the circuit is tested by automatically switching the voltage within a range of, for example, 5%.

[Industrial application field]

TECHNICAL FIELD The present invention relates to a circuit self-diagnosis method, and more particularly to a test for maintenance of equipment.

[Conventional technology]

A conventional data processing device, for example, a terminal device, as shown in FIG.
OM (Read Only Memory) 4
a', RAM (Random Access Me)
mory) 4 b, floppy disk section 4C1
Line control section 4d, keyboard control section 4e, display control section 4
f, a printer control section 4g, etc., and includes a keyboard 4h, a display section 41, a printer 4j, etc. as external devices.

When a device is shipped from the factory, an operation test is performed with the power supply voltage fluctuating by ±5% of the specified value as one of the tests to detect defective products. I'm checking the circuit using voltage.

This circuit check method includes ROM parity check, RAMR/W check, floppy disk R/W check,
We conduct W checks, keyboard tests, display tests, printer printing tests, etc.

[Problem that the invention seeks to solve]

As described above, in the conventional circuit check method, the circuit is operated at the basic voltage, and tests for voltage fluctuations are not performed. As a result, it is not possible to detect components that are in the process of deterioration, and small voltage fluctuations that occur during device operation often cause malfunctions or hardware errors that cause failures.

Therefore, it is required to detect abnormality in the circuit of the device at an early stage and replace it with a normal one.

A test method for this purpose is required.

An object of the present invention is to provide a circuit self-diagnosis method for early detection of such circuit abnormalities.

[Means for solving problems]

In order to achieve the above object, in the present invention, as shown in FIG.
% (for example, α=5), and not only the basic voltage (for example, +5V) but also a voltage of ±α% (for example, +5V) is used for initial tests at power-on and operation tests during maintenance. 25V and +4.75V).

[Effect]

In addition to the basic voltage, tests are also performed at voltages of ±α%, making it possible to detect defective components at an early stage.

〔Example〕

An embodiment of the present invention will be described based on FIGS. 2 and 3 with reference to other countries.

FIG. 2 shows the configuration of an embodiment of the present invention; FIG. 2(a) is a circuit configuration diagram, FIG. 2(b) is an explanatory diagram of control signals to the power supply section, and FIG. 3 is an explanatory diagram of the operation of the present invention. .

In FIG. 2, the same reference numerals as the others indicate the same parts, 5 is a selector, and 6 is a dip switch.

In a device with a basic voltage of +5V, the power supply unit 2 has voltages of +5°25V and +5%, which vary by ±5%, in addition to this basic voltage +5V
It generates an output of 4.75V, and selectively outputs the voltage according to the states of control signals SLO and SLI. As shown in FIG. 2(b), the control signal SL
When O is rlJ, it operates in normal mode and outputs +5V, but when control signal SLO is "0", it operates in voltage fluctuation mode, and if control signal SLI is further rlJ, it outputs +5V of +5%. Outputs .25V and outputs control signal SLI
If is further "0", +4.75V, which is a -5% state, is output.

The processor 3 selectively outputs a control signal so that the control signal 5LO1SLI becomes "1" or "0" during an initial test at power-on and an operation test during maintenance. Chip select signal C8O-C32
It outputs a read/write signal R/W, etc.

The ROM 4a holds a control program for controlling the device 1, and also holds an initial test program and an operation test program during maintenance.

The RAM 4b is used to read and write test data.

The selector 5 selects the power supply section 2 based on the control of the processor 3.
In contrast, the control signal 5LO1SLI is selectively controlled to be "1" or "0".

The DIP switch 6 is a setting switch for operation tests during maintenance, and is normally turned off, that is, in the "0" state, but when it is turned on during maintenance to indicate a change in the power supply and the power is turned on, the processor 3 turns it on. Look +5v, +4.75V,
The output of the power supply unit 2 is sequentially switched and controlled to +5.25V.

Next, the operation of the present invention will be described with reference to the flowchart in FIG. 3, with reference to an example of an initial test performed at the beginning of the - day when finishing the power supply.

(2) First, when the power switch of the power supply is turned on, the precessor 3 performs control based on the initial test program held in the ROM 4a.

Based on this program, first the control signal SLO
Set to "1".

(2) This control signal SLOrlJ causes the power supply unit 2 to output a basic voltage of +5V, and the device 1 operates accordingly. Then, the processor 3 performs self-diagnosis tests such as a RAM ride read test and a timer test based on the initial test program read from the ROM 4a.
If this first test is abnormal, the abnormality is notified by, for example, an alarm or a display on the display unit 41, and a search for the failure is performed.

■ If the first self-diagnosis is normal, the processor 3 sets the control signal SLO to "0" based on the program.
”, set SLl to rlJ. As a result, the power supply section 2 becomes +5
．． 25V is output to each part of the device 1, and in this state a second self-diagnosis test is performed using the initial test program. If this second test is abnormal, this will be notified by the same means as in the case described above.

(2) If the second self-diagnosis is normal, the processor 3 sets the control signals SLO to rOJ and SLI to "0". As a result, the power supply section 2 outputs +4.75V to each section of the device 1, and in this state, the third self-diagnosis test is performed using the initial test program. If this third test is abnormal, this will be reported as in the previous case.

(2) If the third self-diagnosis is normal, the processor 3 sets the control signal SLO to "1" again.

As a result, the power supply unit 2 again outputs the basic voltage +5V to each part of the device 1, and then the operation program is started.

In addition, when performing an operation test during maintenance, the operator turns on the power by turning the dip switch 6 to the on state indicating the point where the power is changed. As a result, processor 3
Read the state of the dip switch 6, and if the bit indicating the power supply change is on, that is, the dip switch 6 is on, the output of the power supply section 2 is set to +5V, +5V, as in the case of FIG.
．． 25V.

+4.75V is sequentially switched at regular time intervals, and in each state, operation tests during maintenance, such as display tests, memory tests, floppy disk tests, keyboard tests, etc., are performed on each operating part to check for failures.

In the above description, an example of a terminal device was explained as the device, but the present invention is of course not limited to this, and the fluctuation range is not limited to ±5% and can be appropriately selected.

〔Effect of the invention〕

According to the present invention, by automatically switching the power supply voltage, it is possible for the user to test against power supply fluctuations, so circuits on the verge of failure or suspicious circuits, devices, etc. can be detected at an early stage. , high reliability can be obtained.

[Brief explanation of the drawing]

Figure 1 is a diagram explaining the principle of the present invention, Figure 2 (a) is a circuit configuration diagram of an embodiment of the present invention, and Figure 2 (b) is a diagram explaining the principle of the present invention.
3 is an explanatory diagram of the control signal to the power supply unit, FIG. 3 is an explanatory diagram of the operation of the present invention, and FIG. 4 is an example of a conventional terminal device. 1--Device, 2--Power supply section 3--Processor 5--Selector 6--DIP switch

Claims (1)

[Claims] A data processing device that is equipped with a processor and that performs self-diagnosis is provided with a power supply unit (2) whose output voltage can be changed by a control signal, and that performs self-diagnosis while the voltage is changed from the basic voltage. A circuit self-diagnosis method characterized by: