KR20000045133A - Method and circuit for diagnosing fault in multi-functional hardware - Google Patents

Abstract

PURPOSE: A method for diagnosing a fault in a multi-functional hardware is provided to recover the fault by checking each sensor channel and an element with a feedback circuit separately comprising as well as a main circuit, and by minutely displaying each sensor channel and an element in a display of an output result. CONSTITUTION: A method for diagnosing a fault in a multi-functional hardware, with a Central Processing Unit(CPU), an Analog to Digital(A/D), and a Digital to Analog(D/A), comprises the steps of: diagnosing a CPU, monitoring the CPU's condition by a watch dog; diagnosing a memory, comparing and diagnosing a data firstly inputted with a data read by inputting a fixed data and then reading a date in a predetermined area of a memory, when a power is on at first, or when an user commend a check during operation; diagnosing a power by reading, after diagnosing a voltage value of each power through a A/D converter; diagnosing the A/D converter and a D/A converter; diagnosing an analog circuit, checking an inputting channel of each analog by comparing the output value, after outputting the voltage value to diagnose through the D/A converter for the input channel asked to check and being inputted through the A/D converter; diagnosing a digital input/output by outputting an output signal for the fault diagnosis to an input terminal in diagnosing an input, and by being received an input for a fault diagnosis from an output terminal in diagnosing an output; and displaying the diagnosed result and exiting.

Description

Fault diagnosis method and its circuit of multifunction hardware

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for diagnosing a failure of various kinds of hardware. In particular, the present invention relates to a method for diagnosing failure of a multifunctional hardware including various types of devices such as an A / D and a D / A converter.

Fault diagnosis is a method of checking the hardware status manually or automatically to check the status of the hardware from time to time to perform the basic functions of the hardware smoothly. There may be a number of ways, including the inclusion of a test function.

In the conventional failure diagnosis method, the test is mainly limited to the CPU board, and when a failure occurs in another part, it is difficult for the user to easily cope with it and hassle of having to inspect the test by a professional engineer. In addition, even if the system is equipped with the function to inspect other parts besides the CPU board, the inspection function is available only on a board basis, and since there is no function to perform detailed inspection for each device, the output result of the inspection is displayed only on a board basis. It is possible. Therefore, in case of system failure, the user has no choice but to replace all the boards in order to repair the system directly. This is not only troublesome to maintain, but also has many disadvantages in terms of cost.

In order to solve the above problems, in the present invention, in addition to the main circuit, the feedback circuit can be separately configured to inspect each sensor channel and device unit, and the expert engineer can display the channel and device unit in detail in the display of the output result. The purpose of the present invention is to facilitate maintenance and repair, and to increase the efficiency in cost reduction.

In order to achieve the above object, in the present invention, the main circuit and the feedback circuit are configured separately so that the state of the main circuit is programmed through the feedback circuit. In particular, in designing the feedback circuit, analog and digital components are separately subdivided, and the sensor channels and device units are precisely diagnosed and the results are displayed for convenience in maintenance.

The main circuit is divided into CPU, memory, display and key input circuit, analog circuit, digital input / output circuit, power supply, and so on. It has the following fault diagnosis function.

The CPU basically has a watch dog function, which always monitors the status. The memory performs the test when the user first turns on the power and when the user issues a test command. Input arbitrary data and read the data from the area again, and compare the first input data with the read data. If the error is normal, the message 'Good' is displayed. If there is an error, the memory device number of the problem area is displayed. do.

In the inspection of the power supply unit, various DC power supplies used in the hardware are inspected. Each DC power source used inside the hardware is connected to each channel of the multiplexer input to the A / D converter inside the circuit. When the test starts, the voltage value of each power source is read through the A / D converter. Message is displayed and the power is displayed to indicate a problem.

The analog circuit includes an A / D converter and a D / A converter, and mainly performs a function of receiving data through several channels from an external sensor. In the present invention, not only basic A / D and D / A converter circuits, but also diagnostic functions are performed on each sensor channel. First of all, the test of A / D converter outputs arbitrary voltage through D / A converter, and the output voltage is input to one channel of A / D converter through the preconfigured circuit. Compare the voltage value input through the A / D converter and if there is a difference, display the number of the corresponding device and take action. As for the test of the D / A converter, similar to the previous method, the D / A converter outputs a voltage of + 5V and the A / D converter simultaneously outputs the voltage input through the D / A and the existing + 5V voltage value. In comparison, it is determined whether the D / A converter is abnormal. And since each sensor value is input through several channels, it uses a multiplexer and converts data by using a signal interface card at the input terminal according to each sensor type. In the present invention, an arbitrary voltage value is output through the D / A converter, and the output voltage is transmitted to the signal interface card of all channels through the feedback circuit. In this state, if the changeover switch on the signal interface card is put in the test mode, the card sends back the voltage value output from the D / A converter instead of the external sensor value and internally compares the voltage value fed back from each channel. If there is a difference, the corresponding channel number is displayed to indicate a problem. This feature can be manually tested by the user at random. In other words, if you want to perform a test on one channel arbitrarily, put the selector switch of the signal interface card corresponding to the desired channel in test mode, and input the desired voltage value from the display and key input unit. This voltage value is fed back to the internal A / D converter via the signal interface card. The feedback voltage value is displayed along with the voltage value input by the user so that the user can check whether there is an abnormality in the corresponding channel by comparing the two voltage values.

The digital input / output circuit consists of a decoder, a buffer, and a latch. In addition to the buffer and latch for basic input / output functions, there is a feedback circuit for troubleshooting. First, in the digital input circuit, the fault diagnosis is to connect the output signal from the output buffer of the feedback circuit to the input terminal of the basic input buffer, and then send out random test data, and then compare the data input through the input buffer with the test data. If is present, the number of the corresponding device is displayed. In the digital output circuit as well, an input buffer for fault diagnosis is connected to the output terminal of the basic output buffer to compare the output data with the feedback data and display the device number of the difference part.

The above-mentioned fault diagnosis function is designed to run automatically after power on self-test at the initial power-up and always check whether there is any problem before the system is started.

1 is an overall configuration diagram of a system according to the present invention.

2 is a block diagram of a circuit for checking an analog line state in accordance with the present invention.

3 is a schematic diagram of a circuit for digital input line state inspection in accordance with the present invention;

4 is a block diagram of a circuit for checking a digital output line state according to the present invention.

Figure 5 is a flow chart for the power on self-test (Power on self-test) function of the present invention.

6 is a flow chart for the power diagnostic function of the present invention.

7 is a flowchart of the A / D converter diagnostic function of the present invention.

8 is a flowchart of a D / A converter diagnostic function of the present invention.

9 is a flow chart for the sensor channel diagnostic function of the present invention.

10 is a flow chart of the memory diagnostic function of the present invention.

11 is a flow chart for the digital input diagnostic function of the present invention.

12 is a flowchart of the digital output diagnostic function of the present invention.

<Description of the code | symbol about the principal part of drawing>

10: power supply 20: motherboard

30: CPU 40: Memory

50: display & key circuit 60: analog circuit

61: A / D converter 62: Multiplexer

63: signal interface card 64: sensor interface terminal

70: digital input / output circuit 71: input buffer

72: external input terminal 73: output buffer

74: external output terminal 80: feedback circuit

81: D / A converter 82: Multiplexer

83: output buffer for fault diagnosis 84: input buffer for fault diagnosis

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is an overall configuration diagram of a system according to the present invention, as shown therein, a power supply unit 10, a mother board 20, a CPU 30, a memory 40, a display and The key input circuit 50, the analog circuit 60, the digital input / output circuit 70, the feedback circuit 80, etc. are comprised.

Power is supplied to each circuit through the motherboard 20, and performs the basic system functions in the CPU 30, memory 40, display and key input circuit 50, and the analog circuit 60 provides an external sensor. Collect the data input through the transfer to the CPU (30). The digital input / output circuit 70 inputs and outputs an on / off signal through an external contact or a relay. The feedback circuit 80 may be an auxiliary circuit for diagnosing whether the above main circuit can be driven normally.

FIG. 2 is a circuit diagram for checking an analog line state. The A / D converter 61 receives a sensor signal of the sensor interface terminal 64 coming from the signal interface card 63 through the multiplexer 62. The D / A converter 81 transmits an output signal for checking the A / D converter and the D / A converter and an output signal for checking each sensor channel through the multiplexer 82.

First, the signal directly connected from the D / A converter 81 to the A / D converter 61 through the multiplexer 82 is used to determine the normal operation of each element of the A / D and D / A converters. The abnormality is determined by comparing the voltage value output through the / A converter 81 with the voltage value detected through the A / D converter 61. The signals supplied from the D / A converter 81 to all the signal interface cards 63 are fed back from each signal interface card 63 and detected by the A / D converter 61 through the sensor input line. By comparing the signal output through the A converter and the signal input through the A / D converter to determine whether each channel is abnormal. In particular, since the signal supplied to the signal interface card 63 is determined by feedback according to the selection of the changeover switch in the card, it is possible to manually select and diagnose only a part of channels.

3 is a circuit diagram for digital input line state inspection, in addition to the basic input buffer 71, there is an output buffer 83 for outputting a fault diagnosis signal. The input buffer 71 has a main function of receiving a signal from an external input terminal 72. The diagnostic function sends out an arbitrary test signal from the output buffer 83 and detects that the signal is fed back through the input terminal 72 through the input buffer 71 and transmits it to the CPU 30. At 30, by comparing the input and output signals, it is determined whether the digital input line is abnormal.

4 is a circuit diagram for checking the digital output line state, in addition to the basic output buffer 73, there is a separate input buffer 84 for feeding back and detecting the output signal. In the output buffer 73, the main function is to export data via the external output terminal 74. The fault diagnosis function detects the signal output to the external output terminal through the output buffer by feeding it back to the input buffer and transmitting the signal to the CPU 30. Then, the CPU 30 checks whether the output signal is normal. It is determined whether the abnormality of.

FIG. 5 is a flowchart illustrating a power on self-test function of an initial power input of the present invention. When power is initially supplied to the system or an automatic test command is issued, a power diagnosis (S10) and A Diagnostics for the / D converter diagnosis (S20), D / A converter diagnosis (S30), sensor channel diagnosis (S40), memory diagnosis (S50), and digital input / output diagnosis (S60, S70) are all performed. If it is determined that there is a failure (S80), the corresponding error message is displayed (S90) and if it is normal, a 'Good' message is displayed (S100).

FIG. 6 is a flowchart illustrating a power diagnosis function of the present invention. When a test is started (33), each voltage value of + 5V, + 15V, and -15V is received through the A / D converter 61 (S11, S12, S13). First, compare + 5V for more than 10% difference (S14). If there is a difference, + 5V error message is displayed (S15). Next, a test of + 15V is performed to compare whether there is a difference of 10% or more (S16). If there is a difference, a + 15V error message is displayed (S17) and -15V is also determined whether there is a difference of 10% or more (S18). If there is, a -15V error message is output (S19).

7 is a flow chart of the A / D converter diagnostic function of the present invention. When the diagnosis is started, the D / A converter 81 outputs an arbitrary voltage value through an internal line (S21). At this time, the A / D converter 61 reads the input voltage value (S22) and transmits it to the CPU 30, and the CPU 30 compares the two values (S23) and checks whether there is a difference of ± 0.1V or more. If there is an error (S24), the corresponding device number is displayed (S25). If there is no error, a 'Good' message is displayed (S26).

FIG. 8 is a flowchart illustrating a diagnosis function of the D / A converter of the present invention. When the diagnosis is started, the D / A converter outputs a value of + 5V through an internal line (S31). At this time, the A / D converter reads the voltage input through the D / A converter and the existing + 5V voltage (S32) and transmits it to the CPU.The CPU compares the output value and the two input values (S33) and differs by more than ± 0.1V. If there is an error after the check (S34), the corresponding device number is displayed (S35). If there is no error, a 'Good' message is displayed (S36).

FIG. 9 is a flowchart of a sensor channel test function of the present invention, which is operated manually unlike other functions described above. When the diagnosis is to be performed, the user puts the switch of the signal interface card 63 corresponding to the channel to be tested in the test mode (S41), selects the desired channel number from the display and the key input unit (S42), and then outputs an arbitrary output. The voltage value is designated and input (S43). At this time, the specified value is immediately transmitted to the signal interface card through the D / A converter (S44), and the signal is fed back from the corresponding card 63 to the A / D converter (S46). The voltage value output here is displayed at the top (S45), and the fed back voltage value is displayed at the bottom (S47). By comparing these two values, the user can manually check whether each channel is operating normally.

10 is a flowchart of a memory diagnostic function of the present invention. When the diagnosis is started, first, the existing data stored in the memory is moved to another area in order to prevent the data from being lost during the test (S51). Next, arbitrary data is input into a specific area of the memory (S52), and data is read from the memory again (S53) and compared with the data previously input (S54). When the two data are compared (S55), if there is a difference, the memory element number of the corresponding area is displayed (S56). If there is no difference, a 'Good' message is displayed (S57). After the test is completed, the existing data, which has been moved to another area, is restored to its original location (S58).

11 is a flowchart of the digital input diagnosis function of the present invention. When the diagnosis is started, the arbitrary data is sent out through the output buffer (S61). At this time, the input buffer reads the output data and transmits it to the CPU (S62). The CPU compares the output data with the incoming data through the input buffer (S63) and determines if there is a difference (S64). If there is a difference, the number of the corresponding device is displayed (S65) and if there is no difference, a 'Good' message is displayed. (S66).

12 is a flow chart of the digital output diagnostic function of the present invention. When the diagnosis is started, the data fed back through the input buffer is read (S71) and transmitted to the CPU, and the CPU compares the output data with the previously fed back data. If there is a difference (S73), the corresponding device number is displayed (S74). If there is no difference, a 'Good' message is displayed (S75).

As described above, the present invention "a method for diagnosing a failure of a multifunctional hardware and its circuit" is a method for checking a failure of various hardware incorporating a microprocessor used in various fields, and the system itself has a built-in function for diagnosing a failure. Even if it is not, it has the advantage of allowing the user to easily determine the fault. In addition, the device and channel unit can be diagnosed in detail, and the result can be displayed by element number or channel number. There are many effects.

Therefore, the fault diagnosis function implemented in the present invention can be applied to any hardware system using a microprocessor, and the side effects such as securing reliability and ease of use can be expected.

Claims (4)

In the failure diagnosis method of the multifunctional hardware including the CPU, A / D, D / A converter, A CPU diagnostic process of always monitoring the state of the CPU by a watch dog function; Memory diagnosis process that inputs random data into a certain area of memory and reads data from the area and compares the first input data and the read data when the power is supplied for the first time and when the user issues a test command during operation. and; Connect various DC power sources used in hardware to receive + 5V, + 15V, -15V input to each channel of A / D converter in the circuit, and read the voltage value of each power source through A / D converter during power diagnosis. A diagnostic procedure for power supply; Connect the output of D / A converter to the input terminal of A / D converter, output the predetermined diagnostic voltage through D / A converter, compare it by input through A / D converter, and break down of A / D converter and D / A converter. A / D, D / A converter diagnostic process for diagnosing the; Input channels to be diagnosed by connecting the outputs of the signal interface card to the inputs of the A / D converters using multiplexers and connecting the outputs of the D / A converters to the input terminals of the signal interface cards using the multiplexers. An analog circuit diagnosis process for outputting a voltage value for diagnosis through the D / A converter, and receiving the input value through the A / D converter, and comparing the output value with each other to diagnose each analog sensor input channel; Each of the digital input / output circuits consists of a feedback output circuit for the fault diagnosis output and a fault diagnosis input buffer.The input diagnosis outputs the fault diagnosis output signal to the input terminal, and the output diagnosis receives the fault diagnosis input from the output terminal. Diagnosing digital input / output with feedback; And displaying a corresponding error message if an error is detected in each of the diagnostic procedures, and performing a diagnostic result displaying process of displaying a normal display and ending the diagnosis. The method of claim 1, wherein the displaying of the diagnosis result is performed. If a failure is detected, the number of the corresponding IC is displayed. In the fault diagnosis circuit of the multifunctional hardware including the CPU, A / D, D / A converter, Connect the output of the D / A converter to an input of the A / D converter, Each signal interface card is provided at the input terminal of each channel according to each sensor type. Each input signal is connected to the input terminal of the A / D converter through a multiplexer to select a channel input from each signal interface card. Connecting the output of the D / A converter to each of the signal interface cards through a multiplexer for selecting an output channel, And a switching switch configured to select an input of a sensor and a failure diagnosis signal output from the D / A converter, respectively, in the signal interface card. Fault diagnosis feedback circuit is configured by connecting fault output / input buffer to digital input / output circuit in parallel. The CPU includes a self-diagnosis function of a CPU using a watchdog function, a power diagnosis function for inputting each voltage level through the A / D converter, and checking the state of each power supply, and writing and reading diagnostic data into a memory area. Memory diagnostic function for diagnosing the error and selecting the diagnostic channel through the multiplexer in the fault diagnosis mode, outputs the fault diagnosis voltage through the D / A converter, and receives the input through the A / D converter and compares the output with the analogue. And a diagnostic program for performing a function of diagnosing a circuit and a function of diagnosing a digital circuit by outputting / receiving a digital signal for fault diagnosis through the digital output / input buffer. The failure diagnosis program of claim 3, wherein The fault diagnosis circuit of the multifunction hardware, characterized in that to perform a fault diagnosis for each device to display the device number when the failure occurs.