design of Remote Fault Diagnosis System for PCB
This paper introduces a PC based serial port test system for remote fault diagnosis of PCB board. It has the characteristICs of advanced design, SIMple structure, powerful functions, high performance price ratio, and is easy to carry The application shows that the proposed design scheme is feasible
PCB board

1. System overall structure design
The PC generates the detection control command of each step according to the detection process file, and sends control commands to the SCM test system through the RS-232C serial interface; After the test is completed, the system receives the measurement results sent by the SCM test system, processes the data, and gives an error Diagnosis conclusion: display the test result PCB in the display window of the system soft panel (operation interface); control the entire detection and diagnosis process of the PCB The system can access the network through network interface equipment to form a SMArt remote fault diagnosis system with network functions, or further evolve into a remote measurement and control system or a remote management system to implement wired/digital wireless channel remote data communication of the measurement and control system Networking and intelligence The networking of the system breaks the geographical and quantitative boundaries of deployment areas and equipment expansion to a certain extent, realizing the sharing of software and hardware resources, and the task and load of the entire network system
The measurement and control instrument system of single chip microcomputer mainly consists of AT89C52 single chip microcomputer, serial communication module, frequency measurement and counting module, voltage measurement module of program controlLED switch matrix and channel control circuit Realize serial communication, measure frequency, voltage, count, and generate signal switching module Control signal The sampling/receiver completes the level conversion, regulates and samples the measured signal under the control of the single-chip microcomputer, and provides the input signal for the measuring circuit of the single-chip microcomputer measurement and control instrument system The excitation signal source is the excitation signal generation circuit under the control of a single chip microcomputer, which provides the required working power or excitation signal for the object to be tested plugged into an external socket The programmable switch matrix is an input/excitation signal output channel/response signal It completes the program control switching of excitation signal of each pin of the external socket, adds the power supply and excitation signal required by the pin, and responds to the frequency or voltage output by the pin Signal output The 24 pin external socket is the interface between the tested object and the SCM measurement and control instrument system, which is used to install a 24 pin universal PCB board to be tested Manual test probe completes signal level sampling of PCB board at specific observation point, and can also input excitation signal according to actual needs to realize manual fault finding
Serial communication module is connected by zero data machine to realize short distance communication, with transmission distance less than 15m, and provides input/output channel for transmitting control commands from PC and measurement data of SCM test system The main control software of the system is composed of PC measurement and control software and MCU test software Among them, PC measurement and control software is written in Microsoft Visual Basic 6 language under Windows environment. 0, and MCU test software is written in MCS-5l combined language The flow chart is shown in Figure 2 The main functions realized by the system are system self check (including power on self check and key press self check), automatic diagnosis and manual diagnosis The application shows that the system has stable performance, reliable operation, friendly man-machine interface, simple operation and maintenance, and portability It has obvious application advantages and broad development prOSPects The system has passed the scientific and technological appraisal organized by relevant organizations The PCB board remote fault diagnosis system adopts the design scheme of PC based serial port test system, which has The characteristics of advanced design, simple structure, powerful functions and high cost performance. It has a good reference value for other similar applications

he above is the explanation given by the editor of pcb circuit board company.
If you want to know more about PCBA, you can go to our company's home page to learn about it.
In addition, our company also sells various circuit boards,
High Frequency Circuit Board and SMT chip are waiting for your presence again.