Anti-interference serial port screen with switching function

Abstract

The utility model discloses an anti-interference serial port screen with a switching function, which belongs to the technical field of serial port screens and comprises a main control board, a main control chip, a first level switching circuit, a first RS232 chip, an 8P flat cable interface and a debugging conversion module are arranged on the main control board, two ends of the first level switching circuit are respectively connected with the main control chip and the first RS232 chip, and the 8P flat cable interface is connected with the debugging conversion module. And the first RS232 chip is connected with the debugging conversion module through the 8P flat cable interface. According to the utility model, through the first level switching circuit and the second level switching circuit, TTL or RS232 level signal output can be automatically switched, traditional tin soldering and tin removing operations are replaced, relatively good application of TTL level signals in long-distance transmission and anti-interference capability is improved, the operation and test of the whole main control board become more stable and reliable, and the cost is reduced. And the subsequent maintenance is relatively simple and controllable.

Description

Technical Field

[0001] The utility model belongs to the technical field of display screens and relates to an anti-interference serial port screen with a switching function. Background Art

[0002] The serial port screen refers to a TFT color LCD display control module with serial port communication. It can be connected to external devices such as PLC, inverter, temperature control instrument, data acquisition module, etc. It is widely used in various display fields such as industrial automation, smart home appliances, transportation tracks, data rooms, charging piles, power medical, shared equipment, etc.

[0003] The existing serial port screen uses TTL level signal output to connect to the PC for network operation, but the single TTL level signal is only suitable for short-distance transmission and is easily interfered by electronic signals, which affects the stability of data transmission.

[0004] The existing serial port screen also reserves soldering points of RS232 components on the circuit board. The soldering points are connected to the TTL end output or disconnected to the RS232 end output after the soldering is removed. Since the test needs to pre-select the TTL end or RS232 end of the solder on the circuit board for level signal output, it can be connected to the external PC to form the corresponding signal reading for testing. This requires soldering or tinning at the soldering points for each test. Both test operations are very troublesome. Repeated soldering or tinning can easily cause the entire circuit board to become abnormal and unstable, which is not conducive to the subsequent repair of the serial port screen that may be recycled and reworked, resulting in high subsequent repair and testing costs. Utility Model Content

[0005] The utility model provides a serial port screen with switching function and anti-interference, aiming to solve the problems that the TTL level signal of the existing serial port screen is difficult to apply to long-distance transmission and has poor anti-interference, and the selection method of soldering or tin removal at preset soldering points is easy to cause abnormality and instability in the entire circuit board, and is more unfavorable for the subsequent repair of the serial port screen that may be recycled and reworked, resulting in troublesome test operation and high subsequent repair costs.

[0006] To achieve the above-mentioned purpose, the utility model provides a serial port screen with switching function and anti-interference, including a main control board, on which a main control chip, a first level switching circuit, a first RS232 chip, an 8P wiring interface and a debugging conversion module are provided. The two ends of the first level switching circuit are respectively connected to the main control chip and the first RS232 chip, and the first RS232 chip is connected to the debugging conversion module through the 8P wiring interface. The first level switching circuit includes a first level enabling switch Q1 and a first relay. The first level enabling switch Q1 is connected to the main control chip and the first relay, and the first relay is connected to the first RS232 chip.

[0007] Preferably, the debugging conversion module includes a second RS232 chip, a second level switching circuit, a USB interface and an adapter, the 8P cable interface is connected to the second level switching circuit through the adapter, the second RS232 chip is connected to the USB interface and the second level switching circuit, wherein the USB interface is used for an external PC.

[0008] Preferably, the second level switching circuit comprises a second level enabling switch Q2 and a second relay, the second level enabling switch Q2 is connected to the main control chip and the second relay, and the second relay is connected to the second RS232 chip.

[0009] Preferably, the main control chip transmits a high level to the second level enable switch Q2, and pin 11 of the second relay is connected to pin 12, and pin 14 is connected to pin 13, so as to drive the second relay to switch to RS232 level signal output; the main control chip transmits a low level to the second level enable switch Q2, and pin 11 of the second relay is connected to pin 10, and pin 14 is connected to pin 15, so as to drive the second relay to switch to TTL level signal output.

[0010] Preferably, the main control chip transmits a high level to the first level enable switch Q1, and pin 5 and pin 6 of the first relay are connected, and pin 8 and pin 7 are connected, so as to drive the first relay to switch to RS232 level signal output; the main control chip transmits a low level to the first level enable switch Q1, and pin 5 and pin 4 of the first relay are connected, and pin 8 and pin 9 are connected, so as to drive the first relay to switch to TTL level signal output.

[0011] Preferably, the main control board is provided with a screen display interface that is compatible with a capacitive touch function, a resistive touch function or a non-touch function, and the main control chip is connected to the screen display interface.

[0012] Preferably, the main control board is provided with an SD memory card slot, an audio output interface, and an RTC clock display element, and the main control chip is connected to the SD memory card slot, the audio output interface, and the RTC clock display element.

[0013] Preferably, it further comprises a shell with a hole on the front end surface, wherein a display screen is fixedly mounted in the front end hole of the shell, the main control board is located in the shell, and the front end surface of the main control board is integrally connected with the display screen.

[0014] The beneficial effects of the utility model compared with the prior art are as follows:

[0015] The utility model provides a serial port screen with switching function and anti-interference, which can automatically switch the level signal output of TTL or RS232 through a first level switching circuit and a second level switching circuit, replacing the traditional soldering and detinning operations, so that the operation and test of the entire main control board become more stable and reliable, and the subsequent maintenance is also relatively simple and controllable. In addition, by utilizing the performance of the first RS232 chip and the second RS232 chip, it can improve the better application of TTL level signals in long-distance transmission and anti-interference capabilities, and improve the reliability and stability of TTL level signal output.

[0016] In order to more clearly illustrate the structural features and functions of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the top view structure of the utility model;

[0018] Figure 2 This is a schematic diagram of the structure of the main control board in the utility model;

[0019] Figure 3 for Figure 2 Schematic diagram of the three-dimensional structure;

[0020] Figure 4 This is a schematic diagram of a first level switching circuit in the utility model;

[0021] Figure 5 is a schematic diagram of a second level switching circuit in the utility model;

[0022] Reference numerals:

[0023] 1. Main control board; 2. Main control chip; 3. First level switching circuit; 4. First RS232 chip; 5. 8P cable interface; 6. Debug conversion module; 7. First relay; 8. Second RS232 chip; 9. Second level switching circuit; 10. USB interface; 11. Adapter interface; 12. Second relay; 13. Screen display interface; 14. SD memory card slot; 15. Audio output interface; 16. RTC clock display element; 17. Shell. DETAILED DESCRIPTION

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of this application; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0025] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0026] To achieve the above purpose, the embodiment of the utility model provides a serial port screen with switching function and anti-interference, referring to Figure 1-5 As shown, it includes a main control board 1, on which a main control chip 2, a first level switching circuit 3, a first RS232 chip 4, an 8P cable interface 5 and a debugging conversion module 6 are provided. The two ends of the first level switching circuit 3 are respectively connected to the main control chip 2 and the first RS232 chip 4, the first RS232 chip 4 is connected to the debugging conversion module 6 through the 8P cable interface 5, the first level switching circuit 3 includes a first level enabling switch Q1 and a first relay 7, the first level enabling switch Q1 is connected to the main control chip 2 and the first relay 7, and the first relay 7 is connected to the first RS232 chip 4.

[0027] Furthermore, the debugging conversion module 6 includes a second RS232 chip 8, a second level switching circuit 9, a USB interface 10 and an adapter 11, the 8P cable interface 5 is connected to the second level switching circuit 9 through the adapter 11, the second RS232 chip 8 is connected to the USB interface 10 and the second level switching circuit 9, wherein the USB interface 10 is used for an external PC, the second level switching circuit 9 includes a second level enabling switch Q2 and a second relay 12, the second level enabling switch Q2 is connected to the main control chip 2 and the second relay 12, and the second relay 12 is connected to the second RS232 chip 8.

[0028] Specifically, refer to Figure 4-5As shown, the main control chip 2 transmits a high level to the first level enabling switch Q1, and the pin 5 of the first relay 7 is connected to the pin 6, and the pin 8 is connected to the pin 7, so as to drive the first relay 7 to switch to the RS232 level signal output; the main control chip 2 transmits a low level to the first level enabling switch Q1, and the pin 5 of the first relay 7 is connected to the pin 4, and the pin 8 is connected to the pin 9, so as to drive the first relay 7 to switch to the TTL level signal output; the main control chip 2 transmits a high level to the second level enabling switch Q2, and the pin 11 of the second relay 12 is connected to the pin 12, and the pin 14 is connected to the pin 13, so as to drive the second relay 12 to switch to the RS232 level signal output; the main control chip 2 transmits a low level to the second level enabling switch Q2, and the pin 11 of the second relay 12 is connected to the pin 10, and the pin 14 is connected to the pin 15, so as to drive the second relay 12 to switch to the TTL level signal output.

[0029] In an optional embodiment, the TTL level signal sent by the main control chip 2 reaches the PC through the USB interface 10. The TTL level signal does not need to pass through the first RS232 chip 4 and the second RS232 chip 8, which is suitable for short-distance PC connection.

[0030] In another optional embodiment, the TTL level signal emitted by the main control chip 2 passes through the first RS232 chip 4 and the second RS232 chip 8, and then reaches the PC from the USB interface 10, which is suitable for long-distance PC connection. The TTL level signal is transmitted with the assistance of the first RS232 chip 4 and the second RS232 chip 8, and the level signal is more stable and reliable during long-distance transmission. Specifically, the main control chip 2 transmits a high level to the first level enabling switch Q1, and pin 5 of the first relay 7 is connected to pin 6, and pin 8 is connected to pin 7, driving the first relay 7 to switch to RS232 level signal output; because the RS232 level signal obtained after switching cannot be directly used for connection to a PC, a low level is transmitted to the second level enabling switch Q2 through the main control chip 2, and pin 11 of the second relay 12 is connected to pin 10, and pin 14 is connected to pin 15, driving the second relay 12 to switch the RS232 level signal obtained after switching to a TTL level signal again and transmit it to the USB interface 10, because the USB data connection line can be connected to a PC to transmit a TTL level signal.

[0031] Furthermore, the main control board 1 is provided with an SD memory card slot 14 , an audio output interface 15 , and an RTC clock display element 16 , and the main control chip 2 is connected to the SD memory card slot 14 , the audio output interface 15 , and the RTC clock display element 16 .

[0032] Furthermore, it also includes a shell 17 with a hole in the front end surface, the front end hole of the shell 17 is fixedly mounted with a display screen, the main control board 1 is located in the shell 17, the front end surface of the main control board 1 is connected to the display screen in one piece, the main control board 1 is provided with a screen display interface 13 compatible with a capacitive touch function, a resistive touch function or a non-touch function, the main control chip 2 is connected to the screen display interface 13, and the display screen is connected to the screen display interface 13. For example, the capacitive touch function means that the screen of the display screen can be touched and clicked by fingers, and can be zoomed in and out by multiple mobile phones; the resistive touch function can only be operated by clicking the screen with a handwriting stylus; the non-touch function means that the screen does not respond to being touched, and the screen cannot be operated by fingers.

[0033] In summary, the utility model provides a serial port screen with switching function and anti-interference. Through the first level switching circuit 3 and the second level switching circuit 9, it can automatically switch the level signal output of TTL or RS232, replacing the traditional soldering and detinning operations. The operation and test of the entire main control board 1 become more stable and reliable, and the subsequent maintenance is also relatively simple and controllable. In addition, by utilizing the performance of the first RS232 chip 4 and the second RS232 chip 8, it can improve the better application of TTL level signals in long-distance transmission and anti-interference capabilities, and improve the reliability and stability of TTL level signal output.

[0034] The technical principle of the utility model is described above in combination with the specific embodiments, which are only the preferred implementation methods of the utility model. The protection scope of the utility model is not limited to the above embodiments. All technical solutions under the idea of ​​the utility model belong to the protection scope of the utility model. Those skilled in the art can think of other specific implementation methods of the utility model without creative labor, and they will fall within the protection scope of the utility model.

Claims

1. A serial port screen with switching function and anti-interference, including a main control board, characterized in that: The main control board is provided with a main control chip, a first level switching circuit, a first RS232 chip, an 8P cable interface and a debugging conversion module. The two ends of the first level switching circuit are respectively connected to the main control chip and the first RS232 chip, the first RS232 chip is connected to the debugging conversion module through the 8P cable interface, the first level switching circuit includes a first level enabling switch Q1 and a first relay, the first level enabling switch Q1 is connected to the main control chip and the first relay, and the first relay is connected to the first RS232 chip.

2. The anti-interference serial port screen with switching function according to claim 1 is characterized in that: The debugging conversion module includes a second RS232 chip, a second level switching circuit, a USB interface and an adapter, the 8P cable interface is connected to the second level switching circuit through the adapter, the second RS232 chip is connected to the USB interface and the second level switching circuit, wherein the USB interface is used for external connection to a PC.

3. The anti-interference serial port screen with switching function according to claim 2 is characterized in that: The second level switching circuit includes a second level enabling switch Q2 and a second relay. The second level enabling switch Q2 is connected to the main control chip and the second relay. The second relay is connected to the second RS232 chip.

4. The anti-interference serial port screen with switching function according to claim 3 is characterized in that: The main control chip transmits a high level to the second level enable switch Q2, and pin 11 of the second relay is connected to pin 12, and pin 14 is connected to pin 13, so as to drive the second relay to switch to RS232 level signal output; the main control chip transmits a low level to the second level enable switch Q2, and pin 11 of the second relay is connected to pin 10, and pin 14 is connected to pin 15, so as to drive the second relay to switch to TTL level signal output.

5. The anti-interference serial port screen with switching function according to claim 1 is characterized in that: The main control chip transmits a high level to the first level enable switch Q1, and pin 5 of the first relay is connected to pin 6, and pin 8 is connected to pin 7, so as to drive the first relay to switch to RS232 level signal output; the main control chip transmits a low level to the first level enable switch Q1, and pin 5 of the first relay is connected to pin 4, and pin 8 is connected to pin 9, so as to drive the first relay to switch to TTL level signal output.

6. The anti-interference serial port screen with switching function according to claim 1 is characterized in that: The main control board is provided with a screen display interface which is compatible with a capacitive touch function, a resistive touch function or a non-touch function, and the main control chip is connected to the screen display interface.

7. The anti-interference serial port screen with switching function according to claim 1 is characterized in that: The main control board is provided with an SD memory card slot, an audio output interface, and an RTC clock display element, and the main control chip is connected with the SD memory card slot, the audio output interface, and the RTC clock display element.

8. The anti-interference serial port screen with switching function according to claim 1 is characterized in that: It also includes a shell with a hole on the front end surface, the front end hole of the shell is fixedly mounted with a display screen, the main control board is located in the shell, and the front end surface of the main control board is integrally connected with the display screen.

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