Relay board of stored program control telephone switchboard
By integrating the Ethernet switch module on the relay board of the program-controlled telephone switch, the direct communication between the switch deployment debugging equipment and the microcontroller is achieved, which solves the complex problem of switch resource occupation and debugging, improves resource utilization and reduces costs.
Patent Information
- Application Number
- CN202420028105.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-05
- Publication Date
- 2024-12-31
- Estimated Expiration
- 2034-01-05
AI Technical Summary
During the debugging process of program-controlled switches, switch resources are occupied, which affects resource utilization, and the debugging process is complicated.
Design a relay board for a program-controlled telephone switch, including a microcontroller, an E1 network transformer, an E1 transceiver module and an Ethernet switch module. The microcontroller and an Ethernet switch module are connected through a serial communication interface. The E1 transceiver module and an E1 network transformer are passed through The serial communication interface is connected, and the PCM board of the E1 network transformer and the program-controlled telephone switch are connected through the PCM bus to realize the switch deployment and debugging equipment and communication with the relay board to avoid external switches.
During the switch debugging process, no switch frame resources are occupied, slot resources are saved, user procurement costs are reduced, and debugging process is simplified.
Smart Images
Figure CN222283309U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of program-controlled telephone exchanges, in particular to a relay board of a program-controlled telephone exchange. Background Art
[0002] The relay board of a program-controlled exchange is a device used to transmit and transfer telephone signals. Its main function is to transfer telephone signals from one line to another to achieve the connection and transfer of telephone communications. In networking applications, the relay board can be used to connect different telephone lines and bring multiple telephone lines together on one switch. In this way, users can make internal calls through the switch and realize the function of telephone interconnection. The relay board can also be used to connect different switches to achieve interconnection between switches, thereby expanding the coverage of the telephone network. In addition, the relay board can also be used to implement some advanced functions, such as call transfer, call waiting, call hold, etc. By configuring the parameters on the relay board, the transmission and transfer of telephone signals can be flexibly controlled to provide more telephone services. In short, the relay board of a program-controlled exchange plays an important role in connecting and transferring telephone signals in networking applications, realizing the interconnection and expansion of the telephone network.
[0003] In the prior art, when a program-controlled switch is debugged, a debugging device needs to be deployed on the switch. The switch board usually occupies a slot in the program-controlled switch frame or an external switch. As a result, the switch resources are occupied during the debugging process, affecting the resource utilization of the switch and making the debugging process complicated. Utility Model Content
[0004] In order to solve the technical problems in the prior art that switch resources are occupied during the debugging process of the switch, affecting the resource utilization of the switch, etc., the utility model provides a relay board for a program-controlled telephone switch.
[0005] The technical solution of the utility model to solve the above technical problems is as follows:
[0006] A relay board of a program-controlled telephone exchange comprises a single-chip microcomputer, an E1 network transformer, an E1 transceiver module and an Ethernet switch module; the single-chip microcomputer is electrically connected to the Ethernet switch module and the E1 transceiver module through a serial communication interface, the E1 transceiver module is electrically connected to the E1 network transformer through a serial communication interface, and the E1 network transformer is connected to a PCM board of the program-controlled telephone exchange through a PCM bus.
[0007] The beneficial effect of the utility model is that by adding an Ethernet switch module to the digital relay board, when the program-controlled telephone switch is being debugged, the switch deployment debugging device is directly connected to the single-chip microcomputer through the Ethernet switch module on the digital relay board, and the switch deployment debugging device can communicate with the single-chip microcomputer on the relay board without an external switch. During the debugging process of the switch, the switch resources, that is, the switch frame, will not be occupied, and the switch frame resources will not be wasted.
[0008] On the basis of the above technical solution, the present invention can also be improved as follows.
[0009] Furthermore, the Ethernet switch module includes an Ethernet switch control chip U1 and a network interface circuit. The Ethernet switch control chip U1 is electrically connected to the single-chip microcomputer via a serial bus, and the network interface circuit is electrically connected to the Ethernet switch control chip U1 via a serial communication interface.
[0010] The beneficial effect of adopting the above further solution is that the storage chip U2 is set to store the configuration information of the Ethernet switch control chip U1.
[0011] Furthermore, the model of the Ethernet switching control chip U1 is IP178G, and the model of the storage chip U2 is 24LC02; the synchronous clock interface of the storage chip U2 is electrically connected to the half-duplex serial interface of the Ethernet switching control chip U1, the serial data interface of the storage chip U2 is electrically connected to the half-duplex serial interface of the Ethernet switching control chip U1, the power supply interface of the Ethernet switching control chip U1 is connected to the power supply, and the power supply interface of the Ethernet switching control chip U1 is electrically connected to the serial data interface of the storage chip U2 through a resistor R72.
[0012] Furthermore, the Ethernet switch module also includes a ground filter circuit and a power filter circuit; the ground filter circuit includes capacitors C82, C83, C84 and C85, the output voltage control port of the Ethernet switch control chip U1 is electrically connected to one end of the capacitor C82, one end of the capacitor C83, one end of the capacitor C84 and one end of the capacitor C85, respectively, and the other end of the capacitor C82, the other end of the capacitor C83, the other end of the capacitor C84 and the other end of the capacitor C85 are all grounded; the power filter circuit includes capacitors C86, C87, C88 and C89. 8. Capacitor C89, capacitor C90 and capacitor C91; the power supply access end of the Ethernet switching control chip U1 is electrically connected to one end of the capacitor C86, one end of the capacitor C87, one end of the capacitor C88, one end of the capacitor C89, one end of the capacitor C90 and one end of the capacitor C91 respectively, the other end of the capacitor C86, the other end of the capacitor C87, the other end of the capacitor C88, the other end of the capacitor C89, the other end of the capacitor C90 and the other end of the capacitor C91 are all grounded, and the power supply access end of the Ethernet switching control chip U1 is connected to the power supply.
[0013] The beneficial effect of adopting the above further solution is that by setting capacitors C82, C83, C84 and C85, the output voltage control port of the Ethernet switch control chip U1 can be filtered to filter AC noise. By setting C86, C87, C88, C89, C90 and C91, AC noise in the power supply can be filtered.
[0014] Furthermore, the network interface circuit includes an Ethernet adapter U3 and a network interface connector CN1; the data transceiver port of the Ethernet adapter U3 is electrically connected to the data transceiver port of the network interface connector CN1, and the Ethernet adapter U3 is electrically connected to the Ethernet switch control chip U1 via a serial communication interface.
[0015] Furthermore, the model of the Ethernet adapter U3 is DP83848CVV, and the model of the network interface connector CN1 is HR911105A.
[0016] Further, the E1 transceiver module includes a transceiver filter and a four-way E1 transceiver U4 of model DS21Q59, and the E1 network transformer model is T1068NL; the transceiver filter includes a resistor R63, a resistor R66, a resistor R67, a resistor R68, a resistor R38, a resistor R39, a resistor R54, a resistor R62, a capacitor C43, a capacitor C44, a capacitor C41 and a capacitor C42; the TTIP1 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through a capacitor C6, and the TTIP2 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through a capacitor C23. The TTIP3 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through the capacitor C27, and the TTIP4 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through the capacitor C39; the TRING1 pin, TRING2 pin, TRING3 pin, TRING3 pin, RTIP1 pin, RTIP2 pin, RTIP3 pin, RTIP4 pin, RRING1 pin, RRING2 pin, RRING3 pin and RRING4 pin of the four-way E1 transceiver U4 are electrically connected to the signal input end of the E1 network transformer respectively;
[0017] One end of the capacitor C43 is grounded, the other end of the capacitor C43 is electrically connected to the RTIP4 pin of the four-way E1 transceiver U4 through the resistor R63, and the other end of the capacitor C43 is electrically connected to the RRING4 pin of the four-way E1 transceiver U4 through the resistor R66;
[0018] One end of the capacitor C44 is grounded, the other end of the capacitor C44 is electrically connected to the RTIP3 pin of the four-way E1 transceiver U4 through the resistor R67, and the other end of the capacitor C43 is electrically connected to the RRING3 pin of the four-way E1 transceiver U4 through the resistor R68;
[0019] One end of the capacitor C41 is grounded, the other end of the capacitor C41 is electrically connected to the RTIP2 pin of the four-way E1 transceiver U4 through the resistor R38, and the other end of the capacitor C41 is electrically connected to the RRING2 pin of the four-way E1 transceiver U4 through the resistor R39;
[0020] One end of the capacitor C42 is grounded, the other end of the capacitor C42 is electrically connected to the RTIP1 pin of the four-way E1 transceiver U4 through the resistor R54, and the other end of the capacitor C42 is electrically connected to the RRING1 pin of the four-way E1 transceiver U4 through the resistor R62.
[0021] The beneficial effect of adopting the above further solution is that the signal transmission stability between the E1 network transformer and the four-way E1 transceiver U4 is improved by setting the transceiver filter.
[0022] Furthermore, it also includes a display panel, and the signal input end of the display panel is electrically connected to the signal output end of the single chip computer.
[0023] The beneficial effect of adopting the above further solution is that by providing a display panel, the information output by the single chip microcomputer can be displayed. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 This is a circuit principle block diagram of the utility model;
[0025] Figure 2 It is the structural principle diagram of the Ethernet switch module;
[0026] Figure 3 It is the circuit schematic diagram of the indicator light circuit;
[0027] Figure 4 is a circuit schematic diagram of a network interface circuit;
[0028] Figure 5 This is the schematic diagram of the connection circuit between the E1 network transformer and the E1 transceiver module. DETAILED DESCRIPTION
[0029] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.
[0030] E1 represents European 30-channel pulse code modulation PCM. The electrical connection in the present invention means electrical connection through a wire or a conductor.
[0031] like Figure 1 As shown, this embodiment provides a relay board of a program-controlled telephone exchange, including a single-chip microcomputer, an E1 network transformer, an E1 transceiver module, an Ethernet switch module and a display panel; the single-chip microcomputer is electrically connected to the Ethernet switch module and the E1 transceiver module through a serial communication interface, the E1 transceiver module is electrically connected to the E1 network transformer through a serial communication interface, and the E1 network transformer is connected to the PCM board of the program-controlled telephone exchange through a PCM bus; the signal input end of the display panel is electrically connected to the signal output end of the single-chip microcomputer. By setting the display panel, the information output by the single-chip microcomputer can be displayed. When the display panel can be a liquid crystal display, the data port of the liquid crystal display is electrically connected to the I / O port of the single-chip microcomputer.
[0032] like Figure 2As shown, in some specific embodiments, the Ethernet switch module includes an Ethernet switch control chip U1, and the Ethernet switch control chip U1 is electrically connected to the single-chip microcomputer through a serial bus. The Ethernet switch module also includes a storage chip U2, and the storage chip U2 is electrically connected to the Ethernet switch control chip U1 through a half-duplex serial bus. The storage chip U2 is configured to store the configuration information of the Ethernet switch control chip U1.
[0033] Specifically, the model of the Ethernet switching control chip U1 is IP178G, and the model of the storage chip U2 is 24LC02; the synchronous clock interface SCL of the storage chip U2 is electrically connected to the half-duplex serial interface MDC of the Ethernet switching control chip U1, the serial data interface of the storage chip U2 is electrically connected to the half-duplex serial interface of the Ethernet switching control chip U1, the power supply interface of the Ethernet switching control chip U1 is connected to the power supply, and the power supply interface of the Ethernet switching control chip U1 is electrically connected to the serial data interface of the storage chip U2 through a resistor R72. The power supply access interface VCC of the storage chip U2 is connected to the power supply PVDD, the PVDD1 pin of the Ethernet switching control chip U1 is connected to the power supply PVDD, and the RESETB pin of the Ethernet switching control chip U1 is connected to the power supply PVDD through a series resistor R55. The F_POWER_OFF pin of the Ethernet switching control chip U1 is grounded through a resistor R58, the AUTO_FACTORY_TEST pin of the Ethernet switching control chip U1 is grounded through a resistor R59, and the F_POWER_OFF_LED pin of the Ethernet switching control chip U1 is connected to the power supply PVDD through a series resistor R57 and a light-emitting diode D1; wherein, the positive electrode of the light-emitting diode D1 is connected to the power supply PVDD, the negative electrode of the light-emitting diode D1 is connected to the series resistor R57, and the negative electrode of the light-emitting diode D1 is grounded through a series resistor R56. The two ends of the crystal oscillator Y2 are electrically connected to the X2 pin and the OSC1 pin of the Ethernet switching control chip U1 respectively, one end of the crystal oscillator Y2 is grounded through a series capacitor C7, and the other end of the crystal oscillator Y2 is grounded through a series capacitor C8. Specifically, the Ethernet switch module further includes capacitor C82, capacitor C83, capacitor C84 and capacitor C85, and the output voltage control port of the Ethernet switch control chip U1 is electrically connected to one end of the capacitor C82, one end of the capacitor C83, one end of the capacitor C84 and one end of the capacitor C85, respectively, and the other end of the capacitor C82, the other end of the capacitor C83, the other end of the capacitor C84 and the other end of the capacitor C85 are all grounded. By setting the capacitor C82, the capacitor C83, the capacitor C84 and the capacitor C85, the output voltage control port of the Ethernet switch control chip U1 can be filtered to filter AC noise.The Ethernet switch module also includes capacitor C86, capacitor C87, capacitor C88, capacitor C89, capacitor C90 and capacitor C91; the power supply access terminal PVDD_LDO of the Ethernet switch control chip U1 is electrically connected to one end of the capacitor C86, one end of the capacitor C87, one end of the capacitor C88, one end of the capacitor C89, one end of the capacitor C90 and one end of the capacitor C91 respectively, and the other end of the capacitor C86, the other end of the capacitor C87, the other end of the capacitor C88, the other end of the capacitor C89, the other end of the capacitor C90 and the other end of the capacitor C91 are all grounded, and the power supply access terminal (PVDD_LDO) of the Ethernet switch control chip U1 is connected to the power supply 3.3V. By setting C86, capacitor C87, capacitor C88, capacitor C89, capacitor C90 and capacitor C91, the AC noise in the access power supply 3.3V can be filtered.
[0034] like Figure 3 As shown, the Ethernet switch module also includes an indicator light circuit, in which one end of a resistor R71, one end of a resistor R73, one end of a resistor R74, and one end of a resistor R75 are all grounded; the other end of the resistor R71 is connected to the power supply PVDD via a resistor R76 and a light-emitting diode D6 connected in series in sequence, the other end of the resistor R73 is connected to the power supply PVDD via a resistor R77 and a light-emitting diode D7 connected in series in sequence, the other end of the resistor R74 is connected to the power supply PVDD via a resistor R78 and a light-emitting diode D8 connected in series in sequence, and the other end of the resistor R75 is connected to the power supply PVDD via a resistor R79 and a light-emitting diode D9 connected in series in sequence.
[0035] like Figure 4 As shown, the network interface circuit includes an Ethernet adapter U3 and a network interface connector CN1; the data transceiver port of the Ethernet adapter U3 is electrically connected to the data transceiver port of the network interface connector CN1, and the Ethernet adapter U3 is electrically connected to the Ethernet switch control chip U1 through a serial communication interface. The model of the Ethernet adapter U3 is DP83848CVV, and the model of the network interface connector CN1 is HR911105A.
[0036] Specifically, the TD+ pin of the Ethernet adapter U3 is electrically connected to the TD+ pin of the network interface connector CN1, the TD- pin of the Ethernet adapter U3 is electrically connected to the TD- pin of the network interface connector CN1, the RD+ pin of the Ethernet adapter U3 is electrically connected to the RD+ pin of the network interface connector CN1, the RD- pin of the Ethernet adapter U3 is electrically connected to the RD- pin of the network interface connector CN1, the LED_LINK / AN0 pin of the Ethernet adapter U3 is electrically connected to the L- pin of the network interface connector CN1, the LED_ACT / COL / AN_EN pin of the Ethernet adapter U3 is electrically connected to the R- pin of the network interface connector CN1, the L+ pin of the network interface connector CN1 is connected to a 3.3V voltage through a series resistor R18, and the R+ pin of the network interface connector CN1 is connected to a 3.3V voltage through a series resistor R17. One end of the capacitor C4 is grounded, the other end of the capacitor C4 is electrically connected to the TD+ pin of the network interface connector CN1 through a series resistor R8, and the other end of the capacitor C4 is electrically connected to the TD- pin of the network interface connector CN1 through a series resistor R9. One end of the capacitor C5 is grounded, the other end of the capacitor C5 is electrically connected to the RD+ pin of the network interface connector CN1 through a series resistor R10, and the other end of the capacitor C5 is electrically connected to the RD- pin of the network interface connector CN1 through a series resistor R15.
[0037] The LED_ACT / COL / AN_EN pin of Ethernet adapter U3 is connected to 3.3V voltage through series resistor R22, the LED_SPEED / AN1 pin of Ethernet adapter U3 is connected to 3.3V voltage through series resistor R40, and the LED_ACT / COL / AN_EN pin of Ethernet adapter U3 is connected to 3.3V voltage through series resistor R41. The two NC pins of Ethernet adapter U3 are connected to 3.3V voltage through series resistor R44 and resistor R45 respectively. The AVDD33 pin and IOVDD33 pin of Ethernet adapter U3 are connected to 3.3V voltage. The PFBIN2 pin, PFBIN1 pin and PFBOUT pin of Ethernet adapter U3 are grounded through series capacitor C17, and the two ends of capacitor C17 are connected in parallel with capacitor C11, capacitor C12 and capacitor C16 respectively.
[0038] like Figure 5As shown, the E1 transceiver module includes a transceiver filter and a four-way E1 transceiver U4 of model DS21Q59, and the E1 network transformer model is T1068NL; the transceiver filter includes a resistor R63, a resistor R66, a resistor R67, a resistor R68, a resistor R38, a resistor R39, a resistor R54, a resistor R62, a capacitor C43, a capacitor C44, a capacitor C41 and a capacitor C42; the TTIP1 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through a capacitor C6, and the TTIP2 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through a capacitor C23. The TTIP3 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through the capacitor C27, and the TTIP4 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through the capacitor C39; the TRING1 pin, TRING2 pin, TRING3 pin, TRING3 pin, RTIP1 pin, RTIP2 pin, RTIP3 pin, RTIP4 pin, RRING1 pin, RRING2 pin, RRING3 pin and RRING4 pin of the four-way E1 transceiver U4 are electrically connected to the signal input end of the E1 network transformer respectively.
[0039] One end of the capacitor C43 is grounded, the other end of the capacitor C43 is electrically connected to the RTIP4 pin of the four-way E1 transceiver U4 through the resistor R63, and the other end of the capacitor C43 is electrically connected to the RRING4 pin of the four-way E1 transceiver U4 through the resistor R66; one end of the capacitor C44 is grounded, the other end of the capacitor C44 is electrically connected to the RTIP3 pin of the four-way E1 transceiver U4 through the resistor R67, and the other end of the capacitor C43 is electrically connected to the RRING3 pin of the four-way E1 transceiver U4 through the resistor R68; One end of the capacitor C41 is grounded, and the other end of the capacitor C41 is electrically connected to the RTIP2 pin of the four-way E1 transceiver U4 through the resistor R38, and the other end of the capacitor C41 is electrically connected to the RRING2 pin of the four-way E1 transceiver U4 through the resistor R39; one end of the capacitor C42 is grounded, and the other end of the capacitor C42 is electrically connected to the RTIP1 pin of the four-way E1 transceiver U4 through the resistor R54, and the other end of the capacitor C42 is electrically connected to the RRING1 pin of the four-way E1 transceiver U4 through the resistor R62. The signal transmission stability between the E1 network transformer and the four-way E1 transceiver U4 is improved by setting the transceiver filter.
[0040] The embodiment of the utility model adds an Ethernet switch module to the digital relay board. When the program-controlled telephone switch is debugged, the switch deployment debugging device is directly connected to the single-chip microcomputer through the Ethernet switch module on the digital relay board, so that the switch deployment debugging device can communicate with the single-chip microcomputer on the relay board without an external switch. During the debugging process of the switch, the switch resources, that is, the switch frame, will not be occupied, and the switch frame resources will not be wasted. Therefore, the four-port switch function is integrated on the digital relay board, saving the slot resources of the program-controlled switch, and the user does not need to purchase a switch separately, thereby reducing the user's procurement cost. It should be noted that the application of IP178G Ethernet switch chip is common knowledge in the art, and its communication with the single-chip microcomputer is consistent with the Ethernet switch chip. In the patent application number CN201220238008.8, the patent name is Gigabit Ethernet switch and network system using the switch, which describes and discloses the connection relationship and application of the Ethernet switch chip. Therefore, the utility model adds an Ethernet switch chip to the traditional relay board circuit, so that the program-controlled telephone switch can communicate with the single-chip microcomputer in the relay board circuit through the added Ethernet switch chip during joint debugging, so as to reduce the occupation of the working Ethernet interface on the program-controlled telephone switch and reduce the waste of Ethernet interface resources. Therefore, the utility model does not involve the improvement of computer programs.
[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the concept and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A relay board for a program-controlled telephone exchange, characterized in that: It includes a single-chip microcomputer, an E1 network transformer, an E1 transceiver module and an Ethernet switch module; the single-chip microcomputer is electrically connected to the Ethernet switch module and the E1 transceiver module through a serial communication interface, the E1 transceiver module is electrically connected to the E1 network transformer through a serial communication interface, and the E1 network transformer is connected to a PCM board of a program-controlled telephone switch through a PCM bus.
2. The relay board of the program-controlled telephone exchange according to claim 1, characterized in that: The Ethernet switch module includes an Ethernet switch control chip U1 and a network interface circuit. The Ethernet switch control chip U1 is electrically connected to the single-chip microcomputer via a serial bus, and the network interface circuit is electrically connected to the Ethernet switch control chip U1 via a serial communication interface.
3. The relay board of the program-controlled telephone exchange according to claim 2, characterized in that: The Ethernet switch module further includes a storage chip U2 , and the storage chip U2 is electrically connected to the Ethernet switch control chip U1 via a half-duplex serial bus.
4. The relay board of the program-controlled telephone exchange according to claim 3, characterized in that: The model of the Ethernet switching control chip U1 is IP178G, and the model of the storage chip U2 is 24LC02; the synchronous clock interface of the storage chip U2 is electrically connected to the half-duplex serial interface of the Ethernet switching control chip U1, the serial data interface of the storage chip U2 is electrically connected to the half-duplex serial interface of the Ethernet switching control chip U1, the power supply interface of the Ethernet switching control chip U1 is connected to the power supply, and the power supply interface of the Ethernet switching control chip U1 is electrically connected to the serial data interface of the storage chip U2 through a resistor R72.
5. The relay board of the program-controlled telephone exchange according to claim 3, characterized in that: The Ethernet switch module also includes a ground filter circuit and a power filter circuit; the ground filter circuit includes capacitors C82, C83, C84 and C85, the output voltage control port of the Ethernet switch control chip U1 is electrically connected to one end of the capacitor C82, one end of the capacitor C83, one end of the capacitor C84 and one end of the capacitor C85, and the other end of the capacitor C82, the other end of the capacitor C83, the other end of the capacitor C84 and the other end of the capacitor C85 are all grounded; the power filter circuit includes capacitors C86, C87, C88, Capacitor C89, capacitor C90 and capacitor C91; the power supply access end of the Ethernet switching control chip U1 is electrically connected to one end of the capacitor C86, one end of the capacitor C87, one end of the capacitor C88, one end of the capacitor C89, one end of the capacitor C90 and one end of the capacitor C91 respectively, the other end of the capacitor C86, the other end of the capacitor C87, the other end of the capacitor C88, the other end of the capacitor C89, the other end of the capacitor C90 and the other end of the capacitor C91 are all grounded, and the power supply access end of the Ethernet switching control chip U1 is connected to the power supply.
6. The relay board of the program-controlled telephone exchange according to claim 2, characterized in that: The network interface circuit includes an Ethernet adapter U3 and a network interface connector CN1; the data transceiver port of the Ethernet adapter U3 is electrically connected to the data transceiver port of the network interface connector CN1, and the Ethernet adapter U3 is electrically connected to the Ethernet switch control chip U1 via a serial communication interface.
7. The relay board of the program-controlled telephone exchange according to claim 6, characterized in that: The model of the Ethernet adapter U3 is DP83848CVV, and the model of the network interface connector CN1 is HR911105A.
8. The relay board of a program-controlled telephone exchange according to any one of claims 1 to 7, characterized in that: The E1 transceiver module includes a transceiver filter and a four-way E1 transceiver U4 of model DS21 Q59, and the E1 network transformer model is T1068NL; the transceiver filter includes resistors R63, R66, R67, R68, R38, R39, R54, R62, capacitors C43, C44, C41 and C42; the TTIP1 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through capacitor C6, the TTIP2 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through capacitor C23, and the four-way E1 transceiver U4 The TTIP3 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through a capacitor C27, and the TTIP4 pin of the four-way E1 transceiver U4 is electrically connected to the E1 network transformer through a capacitor C39; the TRING1 pin, TRING2 pin, TRING3 pin, TRING3 pin, RTIP1 pin, RTIP2 pin, RTIP3 pin, RTIP4 pin, RRING1 pin, RRING2 pin, RRING3 pin and RRING4 pin of the four-way E1 transceiver U4 are electrically connected to the signal input end of the E1 network transformer respectively; One end of the capacitor C43 is grounded, the other end of the capacitor C43 is electrically connected to the RTIP4 pin of the four-way E1 transceiver U4 through the resistor R63, and the other end of the capacitor C43 is electrically connected to the RRING4 pin of the four-way E1 transceiver U4 through the resistor R66; One end of the capacitor C44 is grounded, the other end of the capacitor C44 is electrically connected to the RTIP3 pin of the four-way E1 transceiver U4 through the resistor R67, and the other end of the capacitor C43 is electrically connected to the RRING3 pin of the four-way E1 transceiver U4 through the resistor R68; One end of the capacitor C41 is grounded, the other end of the capacitor C41 is electrically connected to the RTIP2 pin of the four-way E1 transceiver U4 through the resistor R38, and the other end of the capacitor C41 is electrically connected to the RRING2 pin of the four-way E1 transceiver U4 through the resistor R39; One end of the capacitor C42 is grounded, the other end of the capacitor C42 is electrically connected to the RTIP1 pin of the four-way E1 transceiver U4 through the resistor R54, and the other end of the capacitor C42 is electrically connected to the RRING1 pin of the four-way E1 transceiver U4 through the resistor R62.
9. The relay board of a program-controlled telephone exchange according to any one of claims 1 to 8, characterized in that: It also includes a display panel, and a signal input end of the display panel is electrically connected to a signal output end of the single chip computer.