A test method and system for checking the connection relationship of wires inside a device under test in a modular manner

Abstract

The present invention adopts a building block approach to construct a test system with a modular design to check the wire connection relationship inside the device under test. The test module adopts the same hardware system and software design. When the connection test is performed on different devices under test, and the test interface and test amount of the tested device have great changes, the test system only needs to replace the corresponding adapter, add or reduce the test module to adapt to different test needs, and there is no special requirement for the distribution range of the device under test. The system test can also automatically test special networks in the device under test, such as "electricity" and "ground" networks. The present invention adopts the test module to build a ZigBee star wireless network test system in a building block manner to test the wire connection relationship of the device under test. It has a strong test expansion capability and can quickly and accurately test various wire connection relationships inside the cabinet of the device under test without the need for additional testing facilities.

Description

Technical Field

[0001] The invention belongs to the field of testing technology, and in particular relates to a wire connection relationship testing system and method. Background Art

[0002] In many cases, checking the connection relationship of wires in equipment is an important task. A large number of wire checking work is carried out manually, which has the problems of large workload, low efficiency, and large environmental space constraints. Especially when repairing old products, if the original data is incomplete or inaccurate, it is difficult to find out the connection relationship of wires between various hidden connector terminals, and it is particularly difficult to manually check the redundant wires and short-circuited wires in the equipment.

[0003] The use of test equipment that automatically checks the connection relationship of wires can better solve the above problems. Several wire-checking test methods are disclosed in the article "Design and Implementation of Intelligent Wire-Checking Instrument Based on CAN Bus" published in "Now Radar" Issue 08, 2012, "Design of Wire-Checking Recorder" published in "Industrial Control Computer" Issue 07, 2015, and "Research and Design of Wire-Checking Instrument Based on DSP" published in Anhui University's Master's thesis Issue 09, 2014.

[0004] However, this type of automatic line checking equipment generally appears in the form of a traditional cabinet, consisting of a test probe, a test host, and a test computer. The cabinet and test probe composition is fixed, that is, once the design is formed, its maximum test capacity is generally determined. For example, a device can test the connection of 5,000 wire connection points at most. If the device under test needs to test more than 5,000 points, this tester will find it difficult to complete the test work. If the distribution area of ​​the device under test is large, exceeding the common cabinet layout, ordinary automatic line checking equipment will also be difficult to test. Line checking testers often require a large cabinet structure, a large amount of equipment, and are extremely inconvenient to carry. Secondly, many traditional line checking testers use the method of driving the test probe with an excitation signal and detecting the excitation signal with the other probes to check the wire connection relationship of the device under test. If a special network with a large number of tested endpoints connected together is detected, such as the "electricity" and "ground" network, it is often necessary to process in layers because it cannot drive a large number of tested endpoint electrical signals. Therefore, line checking instrument equipment with large-capacity testing capabilities and high test performance is often expensive and bulky, which greatly limits the scope of use and efficiency of automatic line checking equipment.

[0005] At present, modularization is a development direction of instruments, and wireless networking technology provides a new solution for the modularization of test instrument construction. The free addition and subtraction method of building blocks without adding cabinet structure, which only needs to add basic modules, can increase or reduce the composition of instruments, which has considerable benefits in controlling costs and improving efficiency. Wireless networking technology is an important development direction of modular instrument equipment. ZigBee networking technology is a short-range wireless communication technology for low data transmission rate and low power consumption. It has low cost, low price, convenient networking and large network capacity. Its core chip has high cost performance, and only a few peripheral devices are needed to form a ZigBee wireless networking transceiver system. Networking protocol programming can be developed using tools used in integrated development environments. The topology of ZigBee networks can be divided into star networks, tree networks and mesh networks. There are many shelf product networking modules on the market, which are cheap, support ZigBee wireless networking, have a secondary development foundation, and can be used for general star network development applications. The networking module can be installed on the reserved position of the test component PCB board. There is one ZigBee device in the network that is a full-function device (FFD) and acts as a coordinator. The remaining nodes are reduced-function devices (RFD). All nodes are networked and connected to the coordinator. Its biggest advantage is its simple structure, convenient networking, and low power consumption. The development of networking technology provides solid technical support for modular line tracing systems. However, there are currently no wireless networking, modular testing, and automatic line tracing testing methods and related systems in a building block manner. Summary of the invention

[0006] The present invention aims to realize a test method and system for checking the internal wire connection relationship of a tested device in a modular manner.

[0007] The present invention overcomes the shortcomings of the prior art and provides a novel building block-type modular testing method and system for checking the internal wire connection relationship of a tested device.

[0008] 1. Solve the difficulties in testing special networks such as "electricity" and "ground" networks in traditional line-finding test methods;

[0009] 2. Solve the problems of traditional line checking and testing methods, such as large equipment volume, difficulty in expansion, and lack of modularity;

[0010] 3. Solve the problem that some special devices under test are difficult to test due to large distribution range;

[0011] 4. Solve the problems of complex structure of wire tracing equipment, high equipment cost, large equipment quantity and inconvenience in carrying.

[0012] The modular test unit designed with low-cost and low-power chips is used as the test basis. By building the test system in a building block style, it can check the short circuit and open circuit of various connections of the wires inside the cabinet of the tested equipment, and can flexibly adapt to the situation where the test objects of different tested equipment are very different. The test system has no traditional test cabinets, and uses ZigBee wireless networking technology to communicate with each other, with strong test expansion capabilities.

[0013] The present invention adopts a building block approach to construct a test system with a modular design to check the wire connection relationship inside the device under test. The test module adopts the same hardware system and software design. When the connection test is performed on different devices under test, and the test interface and test amount of the tested device have great changes, the test system only needs to replace the corresponding adapter, add or reduce the test module to adapt to different test needs, and there is no special requirement for the distribution range of the device under test. The system test can also automatically test special networks in the device under test, such as "electricity" and "ground" networks. The present invention adopts the test module to build a ZigBee star wireless network test system in a building block manner to test the wire connection relationship of the device under test. It has a strong test expansion capability and can quickly and accurately test various wire connection relationships inside the cabinet of the device under test without the need for additional testing facilities.

[0014] A building block modular test method for checking the internal wire connection relationship of a device under test, the test method comprises the following steps:

[0015] (1) Before testing a new type of device for the first time, it is necessary to evaluate the number of wire connection terminals that need to be tested on the device under test and determine the number of test module units required; and complete the production of a special adapter that matches the test of the device under test. If the same type of device under test has been tested before, this step can be skipped;

[0016] (2) Use an adapter to connect the test terminals of each test module of the test system to the connection terminals of the device under test. At the same time, according to the connection conditions, set the ID number of each test module in the test system in the test order starting from the main module, and manually enter the corresponding connection relationship between the wire terminals of the device under test and the test terminals of the test module into the test computer;

[0017] (3) The test system is powered on, the test system performs self-test, and the test module builds a ZigBee star wireless network;

[0018] (4) The test system tests the special networks in the device under test, such as the wire connection relationship of the "ground" and "electrical" networks of the device under test. The test computer of the test system transmits the test instructions to the main module. The main module transmits the instructions through the wireless network and summarizes the test data and uploads it to the test computer. After parsing, the test computer obtains the list of test terminals connected to the special network: such as the "ground" network (A), the list of test terminals connected to the "electrical" network (B), etc.;

[0019] (5) The test system tests the connection relationship of the wires in the device under test except for the special network. The test computer transmits instructions and summarizes data through the same test path as step (4); the test computer analyzes the data and obtains a connection table (C) of the test terminals with mutual connection relationships.

[0020] (6) The test computer performs a comprehensive analysis based on Table (A), Table (B), Table (C) and the corresponding table of the test system and the terminal connection of the device under test, and generates a standard format measured wire table of the device under test;

[0021] (7) The test computer compares the actual measured wire table with the correct wire table to determine whether there are any wire connection errors in the system equipment under test.

[0022] According to the test method in step (1), the number of required test modules needs to be evaluated before testing, and the corresponding test modules and adapters need to be prepared;

[0023] According to step (2), when the test system is manually connected to the device under test through the adapter, the test module ID numbers are set in order from the main test module as module identifiers, and the connection correspondence between the terminals of the tested wires and the test module terminals is manually entered in the test computer. The main test module ID number is ID "1";

[0024] According to step (3), the test system is powered on, the test system self-checks, and checks whether the test module automatically establishes a ZigBee star wireless network. If the test communication is normal, prepare to start the test;

[0025] According to step (4), the test of the device under test first tests the wire connection relationship of the special network in the device under test. For example, the "ground" network and "electricity" network in the device under test are tested. Before the test, the "ground" network of the test module needs to be connected to a certain point in the special network of the device under test with a wire. The system is powered on, and the special network test program is executed in the computer. The test computer sends an instruction to the test module to collect the electrical signal on the test terminal. The AVR single-chip microcomputer in the main test module receives the test computer instruction through the serial port, and sends the instruction to the test module group through the wireless module of the ZigBee star network. After the AVR single-chip microcomputer in each test module in the group receives the instruction through the wireless module of the network, the FPGA chip in the control module executes the instruction to collect the electrical signal from the test terminal. The collected data is summarized by the AVR single-chip microcomputer and the identifier is added to compile it into a specified format table. The main module collects the test table collected by the modules in the group according to the ID sequence of the test modules in the group through the wireless network, and compiles it into a test table in the group and uploads it to the test computer. The data is analyzed by the test computer to obtain a list of test terminals connected to the special network of the device under test. Such as the list of test terminals connected to the "ground" network of the device under test (A), the list of test terminals connected to the "power" network of the device under test (B), etc. The above tests are carried out separately and in sequence, and before and after each test of the new special network, a new connection should be made or the connection line between the "ground" network of the last test system and the special network of the device under test should be removed.

[0026] According to step (5), the test computer is started to test the connection relationship of all other test terminals connected to the test endpoints after excluding the test terminals connected to the special network in the device under test. The program first sorts such test terminals to obtain the test terminal sorting table required for testing. If there are m test modules in the system, the table is sorted from the first test terminal in the main test module: "01-01" to the last test terminal "m-**" of the test system. The test computer sends instructions to the main test module one by one according to the sorting table, specifying the current test terminal to send a "0" level signal and the remaining test terminals to execute the signal acquisition instructions. The main test module receives the test computer instructions through the serial port and sends the instructions to each test module through the ZigBee wireless network. The AVR microcontroller in each module controls the working mode of the test terminal according to the instructions, records the collected data, and adds a specific identifier to form a test collection table in a specified format. The main test module sends instructions to require the modules in the group to upload the test collection table in order. After receiving the instructions, each test module uploads the test table in order. The main test module summarizes the data and uploads it to the test computer.

[0027] The test computer continuously sends new instructions according to the test sequence table until all test items in the test sequence table have been tested and the corresponding collected data have been summarized in the test computer, and then the data collection work is completed. The test computer analyzes the data and obtains the test terminal connection table (C) with interconnected relationships.

[0028] According to step (6), the test computer program performs a comprehensive analysis based on table (A), table (B), table (C) and the corresponding table of the test system and the terminal connection of the device under test, and generates a standard format measured wire table of the device under test. The actual measurement of the wire relationship of the device under test is completed.

[0029] According to step (7), when the test computer stores the correct wire table of the device under test, the test program compares it with the measured wire table to determine whether there is a wire connection error in the device under test and provide a fault node table.

[0030] A building block type modular test system for testing the internal wire connection relationship of a device under test comprises a hardware part and a software part.

[0031] The hardware part includes hardware devices, and the software part includes scheduling control, communication, data analysis, and display output; under the scheduling control of the software, the hardware devices transmit the sampling data to the analysis software through the communication network, and the analysis software displays and outputs the analysis results.

[0032] The test system hardware includes a test computer, 1~m test modules that can automatically form a network, and a matching adapter for the device under test. The adapter is a special device. Each test module is provided with a unique identifier ID number;

[0033] The test computer is responsible for issuing control instructions and processing test data. The test module unit is responsible for reading the test data signal on the connector endpoint of the device under test through the adapter. The test data is transmitted to the test computer and processed by the software according to the pre-entered test terminal and the device under test endpoint connection correspondence table to form the device under test wire connection relationship table.

[0034] Test module, a single module can test devices with a certain number of connection terminals. The main circuit of the test module hardware consists of three parts: the control circuit based on Atmel's AVR microcontroller and interface circuit, the data acquisition circuit based on Xiline's CyloneⅡ EP4C FPGA chip, and the ZigBee wireless network communication module based on TI's CC2530 chip. When the test system needs to add test modules, the ZigBee wireless network communication module is responsible for networking between various test modules; the microcontroller is responsible for controlling the FPGA integrated circuit that collects data to collect data and upload data summary; the FPGA integrated circuit that collects data sends excitation signals and collects data.

[0035] The FPGA integrated circuit that collects data in the test module uses the I / O pins in the FPGA chip as test terminals, and the pins are connected to weak pull-up resistors. When there is no external electrical signal, the test terminal will collect a high-level signal "1". When a low-level signal is input, a low-level signal "0" is collected. If the two test wire endpoints in the device under test are connected, the collected electrical signals are the same. By sending a "0" level signal to the I / O test terminal, only the terminal connected to it can collect a "0" level signal. The remaining test terminals will only collect high-level signals. The wire connection relationship is judged based on the collected signals "0" or "1".

[0036] When the test system uses multiple test modules for testing, it is necessary to set the ID number of each module as the identification code of the module. The test module with ID number 1 communicates with the test computer as the main test module. While collecting data, it is also responsible for the collection of data and data upload of each module unit of the test system. The networking module is embedded in the PCB board at the reserved position of the test module in the form of a single PCB circuit. The networking module uses a PCB printed antenna. The networking module on the main test module plays the role of a coordinator, and the ZigBee networking modules on the other test modules are simplified functional nodes. All nodes can be automatically networked and connected to the coordinator.

[0037] The software part includes: test module embedded software, network module embedded software, and test computer data processing software. The embedded software installed in the single-chip microcomputer and FPGA involved in each test module unit is the same. When loaded into the test system, the embedded software calls the subroutine module through the set unit ID number, and plays the role of coordinating work according to the system setting.

[0038] The beneficial effects of the present invention are:

[0039] The present invention adopts the building block method to construct the test system, modular design, wireless networking, so that the test system is very simple, greatly simplifying the system expansion requirements, which can greatly improve the efficiency of line checking, and has the characteristics of high investment efficiency, easy expansion, easy to carry, and simple combination, which better solves various problems of previous line checking equipment. It provides a high-efficiency inspection method for checking the electrical connection between the terminals of the cabinet or plug-in box of the tested equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Testing process;

[0041] Figure 2 Special network testing process

[0042] Figure 3Schematic diagram of the connection between the test terminals of the test system and the connection terminals of the tested wires of the device under test

[0043] Figure 4 Test system test schematic diagram

[0044] Figure 5 Test system test connection diagram

[0045] Figure 6 Test module schematic logic block diagram DETAILED DESCRIPTION

[0046] The technical solution provided by the present invention will be described in detail below in conjunction with specific embodiments. It should be understood that the following specific implementation methods are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0047] Example 1

[0048] Combination Figure 1-Figure 5 This embodiment discloses a modular testing method for checking the connection relationship of the tested wires, comprising the following steps:

[0049] (1) Before testing a new type of device for the first time, it is necessary to evaluate the number of wire connection terminals that need to be tested on the device under test and determine the number of test module units required; and complete the production of a special adapter that matches the test of the device under test. If the same type of device under test has been tested before, this step can be skipped;

[0050] (2) Use an adapter to connect the test terminals of each test module of the test system to the connection terminals of the device under test. At the same time, according to the connection conditions, set the ID number of each test module in the test system in the test order starting from the main module, and manually enter the corresponding connection relationship between the wire terminals of the device under test and the test terminals of the test modules into the test computer;

[0051] (3) The test system is powered on, the test system self-checks, and the test module builds a ZigBee star wireless network;

[0052] (4) The test system tests the wire connection relationship of the special networks in the device under test, such as the "ground" and "electrical" networks of the device under test. The test computer of the test system transmits the test instructions to the main module. The main module transmits the instructions and summarizes the test data through the wireless network and uploads it to the test computer. After parsing, the test computer obtains the list of test terminals connected to the special network: such as the "ground" network (A), the list of test terminals connected to the "electrical" network (B), etc.;

[0053] (5) The test system tests the connection relationship of the wires in the device under test except for the special network, and the test computer transmits instructions and summarizes data through the same test path as step (4); the test computer performs data analysis to obtain a connection table (C) of the test terminals with mutual connection relationships;

[0054] (6) The test computer performs a comprehensive analysis based on Table (A), Table (B), Table (C) and the corresponding table of the test system and the terminal connection of the device under test, and generates a standard format measured wire table of the device under test;

[0055] (7) The test computer compares the actual measured table with the correct wire table to determine whether there are any wire connection errors in the tested system equipment.

[0056] Before testing in step (1), it is necessary to evaluate the test volume of the device under test, determine the number of system components, and complete the production of a dedicated adapter that matches the device under test. The system requires at least one test module. When the number of test lead connection nodes required for the device under test is less than the number of test terminals of one test module, there is no need to add another test module, nor is there any need to perform wireless networking steps;

[0057] In step (2), when manually connecting the test system to the device under test through the adapter, the test module ID numbers are set in order starting from the main test module as module identifiers, and the connection correspondence between the terminals of the tested wires and the terminals of the test modules is manually entered into the test computer;

[0058] In step (3), the test system is powered on, the test system performs a self-check, and the test module is checked to automatically establish a ZigBee star wireless network. If the test communication is normal, the test is ready to start;

[0059] In step (4), the test of the device under test first tests the wire connection relationship of the special network in the device under test. For example, the "ground" network and "electricity" network in the device under test are tested. Before the test, the "ground" network of the test module needs to be connected to a certain point in the special network of the device under test with a wire. The system is powered on, and the test computer sends the test module an instruction to read the acquisition test terminal level. The AVR single-chip microcomputer in the main test module receives the instruction and sends the instruction to the test module group through the networked wireless module. After the AVR single-chip microcomputer in each test module in the group receives the instruction through the networked wireless module, the FPGA chip in the control module executes the test terminal acquisition level instruction. The collected data is summarized by the AVR single-chip microcomputer and then an identifier is added to compile it into a specified format table. The main module collects the test tables collected by the modules in the group in sequence through the wireless network, compiles them into a test table in the group and uploads them to the test computer. The test computer analyzes them to obtain a list of test terminals connected to the special network of the device under test. For example, the list of test terminals connected to the "ground" network of the device under test (A), the list of test terminals connected to the "electricity" network of the device under test (B), and so on. The above tests are carried out separately and sequentially, and before and after each test of the new special network, a new connection should be made or the connection line between the "ground" network of the last test system and the special network of the device under test should be removed;

[0060] If the measured connection relationship between the "ground" network and the "electricity" network of the device under test is consistent, it means that the "electricity" and "ground" of the device under test are short-circuited, and the device under test needs to be inspected.

[0061] In step (5), the test computer sorts all the test terminals connected to the endpoints under test after excluding the test terminals connected to the special network in the device under test, and obtains the test sorting table for the required test. If there are m test modules in the system, the table is sorted from the first test terminal in the main test module: "01-01" to the last test terminal "m-**" of the test system. The test system performs the following tasks:

[0062] i) Test command sending

[0063] The test computer sends a test control instruction to the main test module in the test system. The test instruction specifies that the first test terminal arranged in the test sequence table sends a test excitation signal, while other test pins in the sequence table collect power-on signals of the test terminals.

[0064] ii) Test data collection

[0065] After receiving the instruction, the AVR microcontroller of the main test module issues the instruction through the wireless network, and at the same time sends the test excitation signal "0" on the first test terminal of this module according to the instruction, and then collects the level signals of other test terminals in this module, summarizes the collected data into a specified table form, and fills the ID number of this module and the test terminal number that sends the test excitation signal "0" into the specified position in the collection table. The microcontrollers in other test modules in the module group determine whether the test terminal that needs to send the test excitation signal "0" is on this module based on the control instructions received through the wireless network. If it is, it controls this terminal to send the test excitation signal, and the other test terminals of this module collect signals. If not, the signal is collected directly. The AVR microcontrollers of each module fill the ID number of this module, the test terminal number that sends the test excitation signal "0", and the collected data into the specified position in the collection table.

[0066] iii) Test data upload

[0067] After the main test module completes the data collection of this module, it notifies each test module in the group in sequence through the wireless network to upload the data collection table to the main test module. After the main test module summarizes the data, it uploads it to the test computer through the serial port.

[0068] iv) Sequential testing

[0069] The test computer sends an instruction to the main test module in the test system to specify the next test terminal to send a test excitation signal, while other test terminals in the sequence table collect electrical signals on the terminals. Each test module executes the instruction and uploads the collected data.

[0070] The test system carries out tests one by one according to the test sequence list until all test items in the sequence list have been completed.

[0071] After the test is completed, the corresponding collected data have been summarized in the test computer, and the data collection work is completed. The test computer analyzes the data and obtains the test terminal connection table (C) with mutual connection relationship.

[0072] In step (6), the test computer performs a comprehensive analysis based on Table (A), Table (B), Table (C) and the corresponding table of the test system and the terminal connection of the device under test. Based on the principle that the test terminals with a level signal of "0" collected in the same acquisition table are connected to each other, the wire connection relationship table of the device under test can be parsed. After conversion, a wire connection table in a standard format can be obtained, thus completing the actual measurement of the wire relationship of the device under test.

[0073] In step (7), when there is a correct wire table, the test program compares it with the measured wire table to determine whether there is a wire connection error in the device under test and provide a fault node table.

[0074] The modular building block testing method for checking the wire connection relationship of the device under test disclosed in this embodiment can effectively test the wire connection relationship of the device under test in a simple and economical manner.

[0075] Example 2

[0076] Combination Figure 1-Figure 6 This embodiment discloses a modular test system for checking the connection relationship of the tested wires in a building block-like manner. The test system includes a hardware part and a software part.

[0077] The hardware part includes hardware devices, and the software part includes scheduling control, communication, data analysis, and display output; under the scheduling control of the software, the hardware devices transmit the sampling data to the analysis software through the communication network, and the analysis software displays and outputs the analysis results.

[0078] The hardware includes a test computer, 1~m test modules that can automatically form a network, and a matching adapter for the device under test. The adapter is a special device. The test modules all provide a unique identifier, which includes an ID unique number. The matching adapter is responsible for the electrical connection between the test system and the device under test.

[0079] The test computer is a general-purpose computer that can communicate with the main test module through a serial port. The test computer is responsible for the control command issuance and the uploaded test data processing.

[0080] The test computer is responsible for issuing control instructions and processing test data. The test module unit is responsible for reading the test data signal on the connector endpoint of the device under test through the adapter. The test data is transmitted to the test computer and processed by the software according to the pre-entered test terminal and the device under test endpoint connection correspondence table to form the device under test wire connection relationship table.

[0081] Test module, a single module can test devices with a certain number of connection terminals. The main circuit of a single module of the test module hardware consists of three parts: the module control circuit based on Atmel's AVR microcontroller and communication interface, the data collection circuit based on Xiline's CyloneⅡ EP4C FPGA chip, and the ZigBee wireless network communication module with TI's CC2530 chip as the core chip. Devices with a certain number of connection ports can be tested. When the test system needs to add test modules, the ZigBee wireless network communication module is responsible for networking between each test module; the microcontroller is responsible for controlling the data collection and data aggregation and uploading of the FPGA integrated circuit that collects data; the FPGA integrated circuit that collects data sends excitation signals and collects data.

[0082] The test module group consists of multiple hardware structures. The same test modules communicate through the wireless network. The embedded software of the test modules is the same. Each module executes different software modules according to its ID number and control command to achieve system test coordination. When the number of connection ports of the device under test is more than the number of tests of a single test module, the test capacity is expanded by increasing the number of test modules. In a system with m test modules (when testing a device under test that requires multiple test modules), the test module sets a unique identifier ID number. The ID number of the main test module is set to "01" by the personnel before the test, and the others in the group are manually set to "02, 03, ... m" in sequence. The main test module sends commands and collects data to other test modules with built-in wired network communication modules in the group through its own ZigBee wireless network communication module.

[0083] The bidirectional I / O pins in the FPGA chip of the test module are brought out as test terminals, which can send signals and can also be used as signal input endpoints for data collection. The test terminals are connected to pull-up resistors. The connection of the wires is determined by comparing the level signals on the test terminals. Before the test, each test terminal is connected to a tested endpoint of the device under test through an adapter. After power is turned on, when there is no external electrical signal, each I / O test terminal will be pulled up to a high level. At this time, the single-chip microcomputer on the test unit controls the FPGA chip to collect electrical signals from this I / O test terminal, and a high-level signal "1" will be collected. When a low-level signal is input to the I / O test pin, a low-level signal "0" is collected.

[0084] When only one test terminal in the entire test system sends a "0" level signal, then only the test terminal connected to it through a wire can collect the "0" level signal. Since the test terminals of the remaining test modules are not connected to it and no external electrical signals are connected, the test terminals will only collect the high-level signal "1". By summarizing all the data tables collected at the same time, checking the test terminals corresponding to the data "0" signal, the information of the test terminals connected with wires is obtained, and the "0" level signal is sent through different test pins in sequence to obtain a series of test terminal information connected with wires. Then, according to the connection correspondence table between the tested wire terminals and the test module terminals, the connection relationship of the tested wire endpoints of the tested system is inferred.

[0085] The ZigBee wireless network communication module on the module is based on the CC2530 core chip of TI company, and a small number of peripheral devices form the ZigBee wireless networking transceiver system. It adopts a star network, uses the networking module of the shelf products on the market, and conducts secondary development to build the star wireless network of the test system. The networking module is embedded on the PCB board of the reserved position of the line detection test unit in the form of a single-chip PCB circuit. The ZigBee module on the main test module acts as a coordinator in the network, and the ZigBee modules on the other test modules act as a reduced function device (RFD). The coordinator selects a channel to set a unique identifier for this network. The peripheral node joins the network to scan the network to find the coordinator of this network, and sends a network access request. The coordinator agrees to access the network and randomly assigns a 16-bit short address to the node to represent successful access.

[0086] The power supply system has two modes: module-provided battery power supply and common power supply power supply. Modules with their own battery power supply can generally share the ground with the tested equipment.

[0087] The software part of the test system is divided into three parts: ZigBee network module software, test unit test software, and test computer data processing software. The ZigBee network module software is modified and compiled by secondary development of shelf product software. The FPGA chip in the test unit compiles the hardware system with VHDL statements, and the microprocessor AVR chip uses C language to form the single-chip test software. The program in the test computer is an application program written in VC as the development environment and runs under the Windiws xp operating system.

[0088] The test time of this embodiment depends on the number of connection terminals of the system under test. For cascade testing of multiple test units, the acquisition is carried out in parallel, but each test endpoint in the system must be set one by one, and the total test time is equivalent to the sum of the time required for each test unit to acquire the test points of this board. A single test module has 250 test endpoints, and the test time is within tens of milliseconds. Then, the test of a system under test with 1,000 connection terminals requires 4 to 5 test units, and the total acquisition time does not exceed a few hundred milliseconds.

[0089] The data table formed after the collection of a single test unit is a maximum of 250-bit binary table (each bit represents a test terminal collection signal), plus the flag identification code and the specified set endpoint flag, the table data volume is 35 bytes. The ZigBee wireless network can transmit a maximum of 32 bytes per frame of data, so to transmit 35 bytes of data, 2 frames of ZigBee data are required. However, in general, the 240 test terminals will not be fully used, so generally 1 frame of ZigBee data can be used for transmission.

[0090] A single test unit will generate a maximum of 250 data tables (corresponding to 250 test terminals) when completing the test. Testing a system with 1,000 connection terminals will generate 1,000 data tables with a data volume of about 256kb. The transmission rate of the ZigBee wireless network can generally reach more than 20kbps. In addition to the communication format frame required in ZigBee communication, the total time for testing a device with 1,000 connector endpoints is about a dozen seconds at most.

[0091] This embodiment can build a test system in a building block manner, without the need for a traditional cabinet, without system internal connection wires, using a wireless communication network, and making system additions and subtractions extremely convenient, solving the difficulty of expanding the test capability of the previous automatic line-finding test system. At the same time, the basic test module adopts a low-power chip structure and is inexpensive. The corresponding test capability can be provided by adding independent test modules in real time according to the device under test, and the test can be carried out without changing the design and other facilities. It has strong scalability, simple system maintenance, and low use cost.

[0092] The above description is only the best specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

[0093] The contents not described in detail in the specification of the present invention belong to the common knowledge of the professionals in this field.

Claims

1. A modular testing method for checking the connection relationship of wires inside a device under test, characterized in that: The steps of this method are as follows: Step 1: Before testing a new device for the first time, it is necessary to evaluate the number of wire connection terminals that need to be tested on the device under test and determine the number of test module units required; And complete the production of a special adapter that matches the device under test. If the same type of device under test has been tested, this step can be skipped; Before testing, it is necessary to evaluate the number of test modules required and prepare the corresponding test modules and adapters; Step 2: Use an adapter to connect the test terminals of each test module of the test system to the connection terminals of the device under test. At the same time, according to the connection conditions, set the ID number of each test module in the test system in the test order starting from the main module, and manually enter the corresponding connection relationship between the wire terminals of the device under test and the test terminals of the test modules into the test computer; Step 3: Power on the test system, perform self-checks, and test modules to build a ZigBee star wireless network. When the test communication is normal, prepare to start the test. Step 4, the test system tests the wire connection relationship of the special network in the device under test respectively, and the test computer of the test system transmits the test instruction to the main module, and the main module transmits the instruction and summarizes the test data through the wireless network, and uploads it to the test computer; after parsing, the test computer obtains the test terminal list A and the test terminal list B connected to the special network; the test terminal list A and the test terminal list B are respectively: the test terminal list A connected to the "ground" network and the test terminal list B connected to the "electrical" network; Step 5: The test system tests the connection relationship of the wires in the device under test except for the special network. The test computer transmits instructions and summarizes data through the same test path as step 4; the test computer analyzes the data to obtain a connection table C of the test terminals with mutual connection relationships; Step 6: The test computer performs a comprehensive analysis based on Table A, Table B, Table C and the corresponding table of the test system and the terminal connection of the device under test, and generates a standard format measured wire table of the device under test; Complete the actual measurement of the wire relationship of the device under test; Step 7: The test computer compares the measured table with the correct wire table to determine whether there is a wire connection error in the tested system equipment; Among them, in step 4: the test of the device under test first tests the wire connection relationship of the special network in the device under test respectively; before the test, it is necessary to use a wire to connect the "ground" network of the test module to a certain point in the special network of the device under test; the system is powered on, and the special network test program is executed in the computer; the test computer sends an instruction to the test module to collect the power signal on the test terminal; the AVR microcontroller in the main test module receives the test computer instruction through the serial port, and sends the instruction to the test module group through the wireless module of the ZigBee star network. After the AVR microcontrollers in each test module in the group receive the instruction through the wireless module of the network, The FPGA chip in the control module executes the instruction of the test terminal to collect the electrical signal; the collected data is summarized by the AVR microcontroller and then an identifier is added to compile it into a table in a specified format; the main module collects the test tables collected by the modules in the group through the wireless network in the order of the test module IDs in the group, and compiles them into a test table in the group and uploads it to the test computer; the data is analyzed by the test computer to obtain the test terminal list A and test terminal list B connected to the special network of the device under test; the above tests are carried out separately and in sequence, and before and after each test of the new special network, a new connection should be made or the connection line between the "ground" network of the last test system and the special network of the device under test should be removed; In step 5: start the test computer to test the connection relationship of all other test terminals connected to the tested endpoints after excluding the test terminals connected to the special network in the tested device; the program first sorts such test terminals to obtain the test terminal sorting table required for testing; there are m test modules in the system, so the table starts from the first test terminal in the main test module: "01-01" to the last test terminal "m-**" of the test system; the test computer sends instructions to the main test module one by one according to the sorting table, specifying the current test terminal to send a "0" level signal, and the remaining test terminals to execute the signal acquisition instructions; the main test module receives the test computer instructions through the serial port and transmits them through the Zig The Bee wireless network sends instructions to each test module; the AVR microcontroller in each module controls the working mode of the test terminal according to the instructions, records the collected data, and adds a specific identifier to form a test collection table in a specified format; the main test module sends instructions to require the modules in the group to upload the test collection table in sequence, and after receiving the instructions, each test module uploads the test table in sequence, and the main test module summarizes the data and uploads it to the test computer; the test computer continuously sends new instructions according to the test sorting table until all the test items in the test sorting table have been tested and the corresponding collected data have been summarized to the test computer, and then the data collection work is completed; the test computer parses the data to obtain a test terminal connection table C with mutual connection relationships.

2. The method according to claim 1, characterized in that In step 2: when manually connecting the test system to the device under test through the adapter, the test module ID numbers are set in order from the main test module as module identifiers, and the connection correspondence between the terminals of the tested wires and the terminals of the test modules is manually entered in the test computer; The main test module ID is ID "1".

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