Multifunctional serial port and network port combination test device and method
The multi-functional serial port and network port combined testing device solves the problem of separate operation for serial port and network port testing, and realizes integrated compatibility of serial port and network port testing. It is convenient to operate and the test results are accurate and reliable.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-22
- Publication Date
- 2026-03-24
AI Technical Summary
In existing technologies, serial port and network port testing require the use of different testing tools or interfaces, which is cumbersome and lacks compatibility. It cannot simultaneously adapt to multiple types of serial ports and network ports, resulting in incomplete data, complicated operations, and difficulty in meeting the needs of efficient and accurate testing and management.
This invention provides a multi-functional serial port and network port combined testing device. Through multi-signal connectors, RJ45 network interface and signal switching switch, it realizes unified access and switching of serial port and network port signals. Combined with signal filtering and noise reduction, common mode suppression and electrostatic protection modules, it ensures the independence and accuracy of the testing process.
It achieves integrated compatibility for testing various types of serial ports and network ports, without the need to change testing tools or interfaces, making the operation more efficient and the test results more accurate and reliable, and the testing process does not interfere with each other.
Smart Images
Figure CN121728002A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electronic device interface testing technology, specifically to a multifunctional serial port and network port combined testing device and method. Background Technology
[0002] RS232, RS422, and RS485 serial and network ports are core communication interfaces for electronic devices, and their functional effectiveness testing is crucial for device reliability. In existing technologies, serial and network port testing often relies on individual fixtures or interfaces; the approach used in traditional single-detection devices like particle counters also applies here, meaning they function effectively in a stable, single-scenario environment. However, with increasing demands for device testing, traditional methods have revealed limitations. They require frequent fixture changes, suffer from poor interface compatibility, and cannot simultaneously adapt to multiple types of serial and network port testing, resulting in incomplete data, cumbersome operations, and difficulty in meeting the needs for efficient and accurate testing and control. Summary of the Invention
[0003] This application provides a multifunctional serial port and network port combined testing device and method, which solves the technical problem that existing serial port and network port testing requires the use of different testing tools or interfaces, which is cumbersome and lacks compatibility. It achieves integrated compatibility for testing various types of serial ports and network ports, without the need to change testing tools or interfaces, and the operation is more efficient and the testing process does not affect each other.
[0004] In view of the above problems, this application provides a multifunctional serial port and network port combined testing device. The device includes: a multi-signal connector for connecting one serial port signal and multiple network port differential signals of the device under test; an RJ45 network interface; and multiple signal switching switches for selecting whether to route the signals of the multi-signal connector to the serial port test path or the network port test path. The serial port test path includes a signal filtering and noise reduction module and a common-mode rejection module, while the network port test path includes a common-mode rejection module and an electrostatic discharge protection module. By switching the signal switching switches, the test modes for serial port loopback testing and network interface testing are switched without interference between the two processes.
[0005] On the other hand, this application also provides a multi-functional serial port and network port combined testing method, the method comprising: connecting the serial port and network port signals of the device under test to the multi-signal connector; selecting the test path by operating a signal switching switch according to the test type; if testing the serial port, switching to the serial port test path and using a network cable to connect the RJ45 network interface for loopback testing; if testing the network port, switching to the network port test path and using a network cable to connect to the test host or an external network.
[0006] One or more technical solutions provided in this application have at least the following technical effects: In summary, this application achieves compatibility testing of multiple serial ports and network ports by unifying serial port and network port signals into a single device, switching the corresponding switch to select a dedicated test path, and obtaining effective test data for both types of interfaces through targeted signal processing and protection optimization. Combined with the physical isolation design of the path for signal isolation, this enables compatibility testing of multiple serial ports and network ports without the need to change tools or interfaces, making the operation more convenient, efficient, and the results more accurate and reliable.
[0007] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description
[0008] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0009] Figure 1 This is a schematic diagram of a multifunctional serial port and network port merging test device provided in an embodiment of this application.
[0010] Figure 2 This is a flowchart illustrating a multi-functional serial port and network port merging test method provided in an embodiment of this application. Detailed Implementation
[0011] This application provides a multifunctional serial port and network port combined testing device and method, which solves the technical problem that existing serial port and network port testing requires the use of different testing tools or interfaces, which is cumbersome and lacks compatibility. It achieves integrated compatibility for testing various types of serial ports and network ports, without the need to change testing tools or interfaces, and the operation is more efficient and the testing process does not affect each other.
[0012] Example 1, as Figure 1 As shown in the figure, this application embodiment provides a multi-functional serial port and network port merging test device, the device comprising: A multi-signal connector for connecting one serial port signal and multiple network differential signals from the device under test.
[0013] Specifically, first, identify the commonly used serial port signal types and Ethernet differential signal specifications of the device under test (DUT). Select a multi-signal connector adapted to these signal transmissions, ensuring its pin count matches the signal transmission requirements. Plan the connector's signal access channels, reserving access paths for corresponding serial port signals to ensure compatibility with at least two of RS232, RS422, and RS485 signal transmissions. Simultaneously, set up independent access channels for multiple Ethernet differential signals to accommodate the four pairs of differential signal pairs required for Ethernet MDI signals. Assign connector pins according to signal type, clearly distinguishing between serial port signal transmission pins and Ethernet differential signal transmission pins to avoid mutual interference during signal transmission. Connect the serial port signal output terminals of the DUT to the corresponding serial port signal access pins of the multi-signal connector. Then, connect each Ethernet differential signal output terminal of the DUT to a corresponding Ethernet differential signal access pin of the multi-signal connector. This multi-signal connector enables unified access for one serial port signal and multiple Ethernet differential signals from the DUT, laying the foundation for subsequent test path switching.
[0014] One RJ45 network interface.
[0015] In this embodiment, the RJ45 network interface is a standard interface for network connections, widely used in Ethernet and computer networks. It consists of a plug and a socket; the plug has eight recesses and eight contacts.
[0016] Specifically, first, the standard transmission specifications and pin definitions of existing RJ45 network interfaces are clearly defined. An RJ45 network interface that meets Ethernet signal transmission requirements and is compatible with multiple types of processed signal outputs is selected, ensuring that its pin configuration matches subsequent signal transmission needs. Based on the signal type and transmission path at the signal switch output, the pins of the RJ45 network interface are functionally assigned, clearly defining the corresponding access pins for differential network signals and processed serial signals to avoid conflicts between different signal types. The signal lines at the signal switch output, after common-mode rejection, electrostatic discharge protection, or filtering and noise reduction treatment, are then connected one by one to the corresponding pins of the RJ45 network interface according to their assigned functions, ensuring reliable line connections and an unbroken signal transmission path.
[0017] The RJ45 network interface enables connection to external devices. In network port testing scenarios, it can be connected to the test host or external network. In serial port testing scenarios, a loopback link can be built through a network cable, so that the signals of both types of tests can be stably transmitted through this standard interface, providing a unified external connection carrier for test implementation.
[0018] Multiple signal switching switches are used to select whether to route the signals of the multi-signal connector to the serial port test path or the network port test path.
[0019] Specifically, the specifications and quantity of signal switching switches required are first determined based on the signal types and quantities output by the multi-signal connector. Then, considering existing signal switching switch transmission parameter standards, switching devices suitable for the transmission frequency and current requirements of serial port signals and Ethernet differential signals are selected to ensure the switches can stably carry both types of signals without signal loss during switching. The input terminals of each signal switching switch are connected one-to-one with the signal output terminals of the multi-signal connector. Each Ethernet differential signal is connected to the input terminal of an independent signal switching switch, while the serial port signal, after signal filtering and noise reduction, is connected to the corresponding input terminal of the signal switching switch, ensuring the correspondence and reliability of the signal transmission path.
[0020] Next, two output terminals are configured for each signal switch, corresponding to the input terminals of the serial port test path and the network port test path, respectively. The connection relationship between the different output terminals of the switch and the two types of test paths is clearly defined, ensuring clear switching logic. Two stable operating positions are set for each signal switch, each corresponding to the conduction state of one output terminal. This ensures that when the switch is in either position, only one of the serial port test path or the network port test path is activated, achieving physical isolation between the two types of paths. The operating position of the signal switch is operated manually or automatically. When switched to the first position, the differential signal from the network port output by the multi-signal connector is conducted to the network port test path via the switch; when switched to the second position, the serial port signal is conducted to the serial port test path via the switch. This achieves selective routing of the multi-signal connector's signal between the two types of test paths, meeting the testing requirements of different interfaces.
[0021] The serial port test path includes a signal filtering and noise reduction module and a common-mode suppression module, while the network port test path includes a common-mode suppression module and an electrostatic discharge protection module.
[0022] Specifically, serial signals such as RS232, RS422, and RS485 are mostly used internally within devices or in short-distance transmission scenarios. These signals are susceptible to high-frequency noise and interference during transmission. However, due to the relatively enclosed transmission environment, the risk of electrostatic discharge (ESD) is much lower than with directly exposed interfaces. Based on this characteristic, a signal filtering and noise reduction method is adopted. A signal filtering and noise reduction module is built using ferrite beads and capacitors as core components. The ferrite bead is connected in series in the serial signal transmission line, using its high-frequency noise suppression effect to block high-frequency interference signals. Simultaneously, the capacitor is connected in parallel between the line and ground, using its high-frequency pass-through and low-frequency blockage characteristics to filter out noise in the signal. This module is connected between the serial signal output terminal and the signal switching input terminal of a multi-signal connector to preprocess the original serial signal. Subsequently, a common-mode interference suppression method was adopted. A common-mode choke was selected to construct a common-mode suppression module, which was connected in series between the output of the signal switching switch and the RJ45 network interface. The common-mode choke attenuates the common-mode noise in the serial port signal through the principle of electromagnetic induction, while allowing useful differential-mode signals to pass through without attenuation. Combined with the electrostatic discharge risk characteristics of the serial port signal, no additional electrostatic discharge protection components are required. Finally, a serial port test path consisting of a signal filtering and noise reduction module and a common-mode suppression module is formed.
[0023] Next, since the network port signal is essentially a high-frequency differential signal, this type of signal inherently possesses strong anti-interference capabilities, and its transmission link already has a certain anti-interference foundation in its actual design, no additional filtering and noise reduction processing is required. However, the network port interface is usually directly exposed to the outside, making it susceptible to damage from external static electricity. Therefore, a common method of electrostatic discharge (ESD) protection is adopted: an ESD protection module is built using ESD devices. The ESD devices are connected in parallel between the network port signal transmission line and ground. When electrostatic discharge occurs, the ESD devices quickly conduct and discharge the static energy, preventing damage to the interface. Simultaneously, to further suppress common-mode noise in the network port signal, the aforementioned common-mode suppression scheme is used, selecting a common-mode choke as the common-mode suppression module. This choke is connected in series between the output of the signal switching switch and the input of the ESD protection module, enhancing the suppression effect on common-mode interference. Finally, a network port test path consisting of the common-mode suppression module and the ESD protection module is formed.
[0024] By combining signal characteristic analysis, module selection and connection methods, test path structures adapted to serial port and network port signals were designed respectively, achieving the effect of accurately matching the transmission requirements of the two types of signals, simplifying path design and ensuring the stability of test signals.
[0025] The test mode can be switched between serial port loopback test and network interface test by switching the signal switching switch, and the test processes do not interfere with each other.
[0026] Specifically, first, determine the control method for the signal switching switches. A manual or automatic control scheme can be adopted to ensure simple and reliable operation and precise switching of the switch's working position. When a serial port loopback test is required, adjust all signal switching switches to the corresponding on position for the serial port test path using the above control method. At this time, the signal switching switches only conduct the transmission path between the multi-signal connector and the serial port test path, while disconnecting the connection with the network port test path. The serial port signal from the device under test (DUT) is output through the multi-signal connector and then sequentially transmitted through the signal filtering and noise reduction module, the signal switching switches, and the common-mode rejection module to the RJ45 network interface. A network cable is then used to connect to the RJ45 network interface to establish a loopback link, thus achieving the loopback test of the serial port signal.
[0027] When network interface testing is required, adjust all signal switches to the ON position for the corresponding network port test path using the same control method. At this time, the signal switches only connect the transmission path between the multi-signal connector and the network port test path, while disconnecting the connection to the serial port test path. The differential signal from the network port of the device under test (DUT) is output through the multi-signal connector and then sequentially transmitted through the signal switches, common-mode rejection module, and electrostatic discharge (ESD) protection module to the RJ45 network interface. Connect the network cable to the test host or external network to complete the network interface test.
[0028] Next, due to the dual-position design of the signal switching switch, the serial port test path and the network port test path are physically isolated. Only one path is in the conducting state at any given time. The transmission paths of the two types of signals are independent of each other and will not generate signal crosstalk. This ensures that the serial port loopback test and the network interface test do not interfere with each other during the switching process and test implementation, and ensures that both types of tests can be carried out stably.
[0029] Furthermore, the apparatus provided in this application embodiment includes: The signal filtering and noise reduction module includes a ferrite bead and a capacitor, which performs high-frequency noise suppression and clutter filtering; the common-mode suppression module is a common-mode choke, which performs common-mode interference suppression and allows differential-mode signals to pass through; the electrostatic discharge protection module is an ESD device, which protects the interface from damage caused by electrostatic discharge.
[0030] In this embodiment of the application, the ESD device is an electronic component used to protect the interface and internal circuit of electronic devices, which can quickly discharge electrostatic energy during electrostatic discharge to avoid damage to the device.
[0031] Specifically, firstly, based on the transmission frequency and high-frequency noise characteristics of the serial port signal, suitable ferrite beads and capacitors are selected as the core components of the signal filtering and noise reduction module. The ferrite beads are connected in series in the serial port signal transmission line, utilizing their high impedance characteristics to block the transmission of high-frequency interference signals in the line. Simultaneously, the capacitor is connected in parallel between the signal line and ground, leveraging its electrical characteristics of passing high frequencies and blocking low frequencies to absorb and filter out noise mixed in the serial port signal. Through the synergistic cooperation of the ferrite beads and capacitors, high-frequency noise suppression and noise filtering of the serial port signal are achieved.
[0032] Next, considering the characteristics of serial and Ethernet signals—that differential-mode signals are useful signals and common-mode signals are interference signals—a common-mode choke adapted to the transmission parameters of both types of signals is selected as the common-mode suppression module. The common-mode choke is connected in series in the test path. When common-mode noise passes through, the common-mode choke generates a strong electromagnetic induction impedance, attenuating the intensity of the common-mode interference signal. When differential-mode signals pass through, the electromagnetic induction generated by the common-mode choke cancels each other out, resulting in minimal impedance. This ensures that the useful differential-mode signal is transmitted without attenuation, thus achieving the dual effect of common-mode interference suppression and normal differential-mode signal transmission.
[0033] Finally, for scenarios where network interfaces are exposed and susceptible to electrostatic discharge (ESD) damage, ESD devices meeting ESD protection requirements are selected to construct an ESD protection module. The ESD device is connected in parallel between the network port signal transmission line and ground. When external static electricity contacts the network port interface and causes ESD, the ESD device quickly breaks down and conducts, forming an ESD discharge path. This rapidly conducts the electrostatic energy to ground, preventing ESD voltage from damaging the network port interface or electronic components within the path, thus achieving ESD protection for the interface.
[0034] Furthermore, the apparatus provided in this application embodiment includes: Multiple signal switching switches correspond to the differential signal path settings of each network port, and each signal switching switch has a first position and a second position.
[0035] Specifically, firstly, based on the actual network port differential signal transmission specifications, the number of differential signal paths contained in the network port under test is determined, ensuring that the number of signal switching switches is completely consistent with the number of network port differential signal paths, so that each network port differential signal corresponds to an independent signal switching switch. Those skilled in the art can refer to the selection criteria for signal switching switches, and combine the transmission frequency, current carrying capacity requirements, and switching response speed requirements of the network port differential signals to select suitable dual-position switching devices, ensuring that the switch can stably transmit the network port differential signals and the serial port processed signals, and that there is no signal distortion or loss during the switching process.
[0036] Next, connect the input terminal of each signal switch to the corresponding differential signal line of the network port output terminal of the multi-signal connector one by one, ensuring that each network port differential signal can be independently connected to the corresponding switch, avoiding mutual interference between signals from different paths at the input terminal. Configure two independent output terminals for each signal switch, one output terminal connected to the input terminal of the network port test path, and the other output terminal connected to the input terminal of the serial port test path, clearly defining the correspondence between the output terminals and the test paths, so that the signal routing direction is clearly identifiable when the switch is switched.
[0037] Subsequently, two stable operating states, a first position and a second position, are set for each signal switching switch. When the switch is in the first position, its input terminal is connected to the output terminal corresponding to the network port test path; when the switch is in the second position, its input terminal is connected to the output terminal corresponding to the serial port test path. This dual-position design enables a single switch to selectively control the conduction of the two types of test paths, ensuring that each network port differential signal can be switched to the target path according to the test requirements.
[0038] Furthermore, the apparatus provided in this application embodiment includes: The serial port signals include at least two of the three types: RS232, RS422, and RS485.
[0039] In this embodiment, RS232 is a serial data interface standard developed by the Electronic Industries Association (EIA), suitable for short-distance, low-speed asynchronous communication, commonly used in connection scenarios between computers and peripherals such as modems and printers. RS422 is a balanced communication interface standard improved upon RS232, designed to overcome the shortcomings of RS232 in terms of short communication distance and low speed. It supports multi-point reception and a transmission rate of up to 10Mb / s, and is widely used for short-to-medium distance data transmission between industrial devices. RS485 is a serial data interface standard extended from RS422, adding multi-point bidirectional communication capabilities, allowing multiple transmitters to connect to the same bus, and possessing strong driving capabilities and conflict protection features. It is suitable for long-distance multi-device interconnection scenarios such as industrial control and IoT terminals.
[0040] Specifically, RS232, RS422, and RS485 are the three most widely used serial port types in electronic devices. Different devices will be configured with one or more of these serial ports depending on the usage scenario. To meet the serial port testing needs of most devices, it is determined that the device must be compatible with at least two of these three types. Based on the signal transmission characteristics of the three serial ports, including existing standards such as signal voltage range, pin definitions, and transmission rates, corresponding signal access paths are planned in the multi-signal connector. Independent transmission pins are reserved for each target compatible serial port to ensure that the access of different types of serial port signals does not conflict. The reserved pins of the multi-signal connector are connected to the corresponding input terminals of the signal filtering and noise reduction module of the serial port test path, so that the different types of serial port signals can be suppressed for high-frequency noise and filtered out by this module.
[0041] Through the above pin planning and circuit connection design, the device can be adapted to the access and testing of at least two of the three types of serial port signals: RS232, RS422, and RS485, covering mainstream serial port testing scenarios and improving the versatility of the device.
[0042] Furthermore, the apparatus provided in this application embodiment includes: The network port differential signal is an Ethernet MDI signal, which includes four pairs of differential signal pairs, and each pair of differential signals is connected to one of the signal switching switches.
[0043] In this embodiment, the Ethernet MDI signal is the interface signal connecting the Ethernet PHY layer and transmission media such as twisted pair cables. It is used to realize signal transmission, reception, and line sequence adaptation, and is the core signal for network device port data transmission.
[0044] Specifically, firstly, based on existing Ethernet transmission technology standards, the differential signal for the network port adopts the widely used Ethernet MDI signal. This signal is the core signal connecting the Ethernet PHY layer and the transmission medium, and its transmission specifications have formed a unified standard within the industry, adapting to the network port signal output characteristics of most network devices. According to the technical specifications of the Ethernet MDI signal, its standard transmission structure includes four pairs of differential signal pairs. This configuration can meet the speed and stability requirements of Ethernet data transmission. Therefore, the composition of the differential signal for the network port in the device is determined to be four pairs of differential signal pairs.
[0045] Following the design principles of signal switching, to ensure the independence of each differential signal pair transmission and the accuracy of switching, four signal switching switches are selected based on the number of four differential signal pairs, ensuring that the number of switches perfectly matches the number of differential signal pairs. Each pair of Ethernet MDI differential signal lines corresponding to the output of the multi-signal connector is connected one-to-one to the input of a signal switching switch, ensuring that each differential signal pair can independently access its corresponding switch and avoiding crosstalk between different signal pairs during transmission.
[0046] By determining the signal type, matching the number of signals, selecting the switch, and connecting the lines as described above, each pair of Ethernet MDI differential signals corresponds to an independent signal switching switch. This lays the foundation for subsequent signal routing between different test paths through switch switching and ensures the orderly switching between network port testing and serial port testing.
[0047] Furthermore, the apparatus provided in this application embodiment includes: The signal filtering and noise reduction module is connected between the serial port signal output terminal of the multi-signal connector and the input terminal of the signal switching switch.
[0048] Specifically, based on the existing characteristics of serial port signal transmission, serial port signals are prone to carrying high-frequency noise and spurious waves after being output from the device under test. If such interference enters the signal switching switch or subsequent path, it will affect the test accuracy. Therefore, it is necessary to complete the filtering and noise reduction process before the signal enters the switching stage. It is determined that the intervention node of the signal filtering and noise reduction module should be located between the multi-signal connector and the signal switching switch.
[0049] First, based on the pin definitions of the serial signal output of the multi-signal connector and the input parameters of the signal filtering and noise reduction module, select appropriate wire specifications to ensure that the impedance characteristics of the wires match the requirements of serial signal transmission and avoid introducing additional interference. Then, solder the input pins of the signal filtering and noise reduction module to the serial signal output pins of the multi-signal connector one-to-one using wires. During soldering, ensure that the solder joints are firm and free of gaps, and maintain a safe distance between adjacent solder joints to prevent signal short circuits.
[0050] After completing the input connection, solder the output pins of the signal filtering and noise reduction module to the input pins of the signal switch in the same manner to ensure that each filtered serial signal can be accurately connected to the corresponding channel of the signal switch. After the connection is completed, use a continuity test tool to check the connection line to confirm that the lines between the signal filtering and noise reduction module, the multi-signal connector, and the signal switch are all conductive and there are no open circuits or poor contact issues.
[0051] Through the above connection design and testing steps, the serial port signal can be directly processed by the filtering and noise reduction module after being output from the multi-signal connector, and then transmitted to the signal switching switch. The interference filtered out in advance will not enter the subsequent path with the signal, thus ensuring the accuracy of the serial port test.
[0052] Furthermore, the apparatus provided in this application embodiment includes: The common-mode suppression module and the electrostatic discharge protection module are connected between the output terminal of the signal switching switch and the RJ45 network interface.
[0053] Specifically, based on the requirement to further optimize transmission quality after signal switching, the common-mode rejection module needs to suppress interference for both the serial port and network port signals after switching, while the electrostatic discharge (ESD) protection module only provides protection for the network port signal. Therefore, it is determined that the two are connected in series between the output of the signal switching switch and the RJ45 network interface, forming a transmission link of switching switch - common-mode rejection module - ESD protection module / RJ45 interface. Based on the pin distribution and signal type of the signal switching switch output, a common-mode choke matching the signal transmission frequency and current parameters is selected as the common-mode rejection module. Simultaneously, ESD devices conforming to the ESD protection level of the network port are selected to ensure that the module performance is compatible with the signal characteristics.
[0054] First, solder the input pins of the common-mode rejection module to the output pins of the signal switching switch one by one using wires. Lead-free solder is used during soldering, and the temperature and time of the solder joints are carefully controlled to avoid cold solder joints or burn-through, ensuring that each signal can independently enter the common-mode rejection module. The output of the common-mode rejection module is divided into two paths: one is directly connected to the corresponding pin of the serial port signal of the RJ45 network interface, and the other is connected to the input pin of the electrostatic discharge (ESD) protection module. Then, solder the output pin of the ESD protection module to the corresponding pin of the network port signal of the RJ45 network interface, ensuring that the network port signal is processed by both common-mode rejection and ESD protection before output. After connection, use a continuity tester to check the continuity of each line to confirm there are no open or short circuits. Simultaneously, verify the common-mode rejection effect using an anti-interference tester and verify the protection performance using an ESD tester to ensure that the module connection meets design requirements.
[0055] The above connection method ensures that the switched signal is processed before being transmitted to the RJ45 network interface, which not only guarantees the purity of the signal but also avoids electrostatic damage, providing link support for the accuracy of subsequent tests.
[0056] In summary, the multifunctional serial port and network port merging test device provided in this application has the following technical effects: This application uses a multi-signal connector to access serial port signals and Ethernet MDI differential signals. After signal filtering, noise reduction, common-mode suppression, and electrostatic protection, the corresponding test path is selected through a signal switching switch. It is compatible with multiple serial port and network port signals. Each module is connected in a specific position to achieve interference-free switching between serial port loopback and network port testing. This eliminates the need to change interfaces, making the operation convenient and the results accurate.
[0057] Example 2, as Figure 2 As shown, based on the same inventive concept as the aforementioned Embodiment 1, this application provides a multi-functional serial port and network port combined testing method, the method comprising: Connect the serial port and network port signals of the device under test to the multi-signal connector; select the test path by operating the signal switch according to the test type; if testing the serial port, switch to the serial port test path and use a network cable to connect the RJ45 network interface for loopback testing; if testing the network port, switch to the network port test path and use a network cable to connect to the test host or external network.
[0058] Specifically, firstly, based on the serial port signal type and network port signal specifications of the device under test (DUT), the serial port signal output terminal of the DUT is connected to the corresponding pin of the serial port of the multi-signal connector one by one using wire connection. At the same time, the differential signal output terminal of the network port of the DUT is connected to the corresponding pin of the network port of the multi-signal connector. During the connection process, ensure that the pins are correctly matched and the wires are firmly in contact to avoid signal transmission interruption or distortion.
[0059] Then, determine the type of test to be performed based on the actual testing requirements, and operate the signal switching switches manually or automatically. If a serial port test is selected, adjust all signal switching switches to the second position; if a network port test is selected, adjust all signal switching switches to the first position, ensuring that the switch positions accurately correspond to the target test path and that the path is effectively conductive.
[0060] After switching to the serial port test path, select a standard network cable to connect the device's RJ45 network interface to both ends of the required loopback link for testing, thus constructing a complete serial port loopback transmission path. On the test host, use the serial port test setup method, open the serial port test mode, configure the transmission parameters matching the serial port signal under test, and receive the loopback transmitted serial port signal through the host to complete the tests for serial port signal connectivity, transmission stability, and other indicators.
[0061] After switching to the network port test path, insert one end of the network cable into the device's RJ45 network interface, and connect the other end to the test host or an external network according to the test requirements. If connected to a test host, start a commonly used network testing tool on the host, configure the corresponding network parameters, and test the transmission rate and connectivity of the network port signal. If connected to an external network, verify the normal communication function of the network port through network communication status detection.
[0062] By following the steps of signal access, path selection, and targeted testing, combined with connection methods, switching operations, and testing techniques, it is possible to complete serial port and network port testing on the same device without changing the interface. Moreover, the testing process does not interfere with each other, the operation is convenient, and the test results are accurate and reliable.
[0063] Furthermore, the method provided in this application embodiment includes: When the signal switching switch is in the first position, the differential signal of the network port connected to the multi-signal connector is routed to the RJ45 network interface through the common-mode rejection module and the electrostatic discharge protection module for network testing or communication.
[0064] Specifically, first, adjust all signal switchers to the first position using either manual toggling or automatic triggering. After operation, verify the switch status using a multimeter's continuity test function to ensure complete continuity between the switch input and the network port test path output, preventing signal transmission abnormalities due to poor switch contact. The differential signal of the device under test's network port, i.e., the Ethernet MDI signal, is connected via a multi-signal connector and then directly connected to the input of the corresponding signal switch using wires. After passing through the switch, the signal enters the common-mode rejection module. This module is a common-mode choke connected in series, utilizing electromagnetic induction to attenuate common-mode noise in the signal while ensuring that useful differential-mode signals pass through without attenuation, thus improving signal transmission purity.
[0065] Then, the differential signal from the network port, after common-mode rejection processing, is connected to the electrostatic discharge (ESD) protection module via a wire. This module is an ESD device connected in parallel between the signal line and ground. When electrostatic discharge occurs, the ESD device quickly conducts, forming a discharge path to guide the electrostatic energy to ground, preventing damage to the interface and subsequent circuitry. The ESD-protected differential signal is then precisely connected to the corresponding pins of the RJ45 network interface using the same wire soldering method. For network testing, a standard network cable is used to connect the RJ45 interface to the test host. The network test tool is then started on the host, and the parameters are configured before testing. For communication, data transmission can be achieved by directly connecting to an external network via a network cable.
[0066] By controlling switch positions, handling modules specifically, and standardizing connections, combined with signal processing and connection methods, stable transmission of differential signals from the network port was achieved, ensuring the accuracy of network testing and the security of the interface.
[0067] Furthermore, the method provided in this application embodiment includes: When the signal switching switch is in the second position, the serial port signal connected to the multi-signal connector is routed to the RJ45 network interface through the signal filtering and noise reduction module, the signal switching switch and the common mode suppression module in sequence for serial port loopback testing.
[0068] Specifically, firstly, all signal switching switches are adjusted to the second position using either manual toggle or automatic triggering. Afterward, a multimeter is used to test each path in continuity mode to confirm effective continuity between the switch input and the serial port test path output, preventing signal transmission interruption due to switch misalignment. The serial port signal from the device under test is connected via a multi-signal connector and then directly transmitted to the signal filtering and noise reduction module via a wire. In this module, ferrite beads are connected in series to the signal line, utilizing their high-frequency, high-impedance characteristics to block high-frequency noise; capacitors are connected in parallel between the line and ground, using their high-frequency pass-through and low-frequency block-through characteristics to filter out noise, significantly improving the purity of the processed serial port signal.
[0069] Then, the filtered and noise-reduced serial port signal is connected to the signal switching switch in the second position via a wire, which then turns on the common-mode rejection module. The common-mode rejection module is a common-mode choke connected in series. It attenuates common-mode interference in the signal through electromagnetic induction while allowing useful differential-mode signals to pass through without attenuation, further optimizing signal quality. The serial port signal that has undergone common-mode rejection processing is then soldered and connected to the designated pins of the RJ45 network interface using the corresponding wires. A loopback link is created using a standard network cable, shorting the transmit and receive pins of the RJ45 network interface. On the test host, the serial port test mode is enabled, and parameters such as baud rate and data bits are configured to match the serial port under test. The loopback transmission signal is then received to complete the test.
[0070] By employing switch control, signal segmentation processing, and standardized loopback setup procedures, combined with connection and testing methods, stable transmission and accurate testing of serial port signals were achieved, enabling serial port loopback testing to be completed without changing the interface.
[0071] Through the foregoing detailed description of a multi-functional serial port and network port merging test device, those skilled in the art can clearly understand that the multi-functional serial port and network port merging test method in this embodiment is similar to the method disclosed in Embodiment 2. Since it corresponds to the device disclosed in Embodiment 1, it has corresponding execution steps and technical effects. For relevant details, please refer to the system section description.
[0072] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A multifunctional serial port and network port combined testing device, characterized in that, The device includes: A multi-signal connector for connecting one serial port signal and multiple network differential signals from the device under test; One RJ45 network interface; Multiple signal switching switches are used to select whether to route the signals of the multi-signal connector to the serial port test path or the network port test path. The serial port test path includes a signal filtering and noise reduction module and a common-mode rejection module, and the network port test path includes a common-mode rejection module and an electrostatic discharge protection module. The test mode can be switched between serial port loopback test and network interface test by switching the signal switching switch, and the test processes do not interfere with each other.
2. The multifunctional serial port and network port merging test device as described in claim 1, characterized in that, The signal filtering and noise reduction module includes a magnetic bead and a capacitor, and performs high-frequency noise suppression and clutter filtering. The common-mode suppression module is a common-mode choke, which performs common-mode interference suppression and allows differential-mode signals to pass through; The electrostatic discharge protection module is an ESD device that protects the interface from damage caused by electrostatic discharge.
3. The multifunctional serial port and network port merging test device as described in claim 1, characterized in that, Multiple signal switching switches correspond to the differential signal path settings of each network port, and each signal switching switch has a first position and a second position.
4. The multifunctional serial port and network port merging test device as described in claim 1, characterized in that, The serial port signals include at least two of the three types: RS232, RS422, and RS485.
5. The multifunctional serial port and network port merging test device as described in claim 1, characterized in that, The network port differential signal is an Ethernet MDI signal, which includes four pairs of differential signal pairs, and each pair of differential signals is connected to one of the signal switching switches.
6. The multifunctional serial port and network port merging test device as described in claim 1, characterized in that, The signal filtering and noise reduction module is connected between the serial port signal output terminal of the multi-signal connector and the input terminal of the signal switching switch.
7. The multifunctional serial port and network port merging test device as described in claim 1, characterized in that, The common-mode suppression module and the electrostatic discharge protection module are connected between the output terminal of the signal switching switch and the RJ45 network interface.
8. A multi-functional serial port and network port combined testing method, characterized in that, When applied to a multi-functional serial port and network port merging test device as described in any one of claims 1-7, the method includes: Connect the serial port and network port signals of the device under test to the multi-signal connector; The test path is selected by operating the signal switching switch according to the test type; If testing the serial port, switch to the serial port test path and use a network cable to connect to the RJ45 network interface for loopback testing; If testing a network port, switch to the network port test path and connect it to the test host or external network using a network cable.
9. The multi-functional serial port and network port combined testing method as described in claim 8, characterized in that, When the signal switching switch is in the first position, the differential signal of the network port connected to the multi-signal connector is routed to the RJ45 network interface through the common-mode rejection module and the electrostatic discharge protection module for network testing or communication.
10. The multi-functional serial port and network port combined testing method as described in claim 8, characterized in that, When the signal switching switch is in the second position, the serial port signal connected to the multi-signal connector is routed to the RJ45 network interface through the signal filtering and noise reduction module, the signal switching switch and the common mode suppression module in sequence for serial port loopback testing.