A hardware circuit and control method for anti-electromagnetic interference of a touch screen

Abstract

A hardware circuit and control method for anti-electromagnetic interference of a touch screen. The circuit includes: a touch screen, a controller, and a diode; the touch screen and the controller are connected through a communication line, and the communication line includes an SDA data line and a reset control line; the SDA data line and the reset control line are connected through the diode; the controller is used to receive touch screen signals, and when data anomalies are detected, the disturbed touch screen is reset and restarted through the diode. Through the judgment of anomalies and subsequent reset of the chip implemented by the control software of the present invention, in cooperation with the improvement of the touch screen control circuit, the occurrence of the situation where the touch screen does not work due to electromagnetic interference can be effectively reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of electronic engineering, and more specifically, relates to a method and a hardware circuit for anti-electromagnetic interference of a touch screen. Background Art

[0002] Touch screens are widely used in the industrial field and are essential important components for human-computer interaction in various instrument and device equipment. The electromagnetic field environment in the industrial field is complex, and whether the touch screen can work properly in such an electromagnetic environment is a matter that every product designer must seriously consider.

[0003] The electromagnetic interference sources in a touch screen system may come from multiple aspects, including power supplies, signal lines, grounding systems, etc. Power supply interference such as unfiltered switched-mode power supply noise, signal line interference such as electromagnetic radiation and coupling, and imperfect grounding systems may all cause electromagnetic interference. Under strong electromagnetic interference, mainly the interference of electrostatic discharge on the touch screen will cause the I2C bus to work abnormally or not work. The phenomenon is that the controller can receive an interrupt response signal, but there is no SDA data. Especially in the case of 6KV contact discharge and 8KV air discharge, the touch screen will show a black screen and touch failure, and cannot be restored.

[0004] To reduce electromagnetic interference, more optimizations need to be made in hardware design and layout, such as using isolation transformers, filters, ferrite beads, and capacitors. These measures will increase the complexity and cost of the system, and the effect may not be very good, and the touch screen will still malfunction.

[0005] The prior art document (CN118689345A) discloses an anti-interference circuit device for a capacitive touch screen in a complex environment. This document mainly discharges or shields external interference signals through a complex hardware circuit and then resets through a reset circuit. The hardware cost is high, and the system complexity is too high. Summary of the Invention

[0006] To solve the deficiencies in the prior art, the present invention provides a hardware circuit and a control method for anti-electromagnetic interference of a touch screen.

[0007] The present invention adopts the following technical solutions.

[0008] The first aspect of the present invention provides a hardware circuit for anti-interference of a touch screen, including: a touch screen, a controller, and a diode;

[0009] The touch screen and the controller are connected through a communication line, and the communication line includes an SDA data line and a reset control line;

[0010] The SDA data line and the reset control line are connected through a diode;

[0011] The controller is used to receive the touch screen signal. When data anomaly is detected, the touch screen that is interfered is reset and restarted through a diode.

[0012] The SDA pin of the touch screen is connected to the SDA pin of the controller through the SDA data line, and the SCL pin of the touch screen is connected to the SCL pin of the controller through the SCL clock line.

[0013] The INT pin of the touch screen is connected to the INT pin of the controller, and the RST pin of the touch screen is connected to the RST pin of the controller through the reset control line.

[0014] The second aspect of the present invention provides a hardware circuit control method for anti-electromagnetic interference of a touch screen. Based on the above-mentioned hardware circuit for anti-electromagnetic interference of a touch screen, it is characterized by including:

[0015] When a touch occurs, the touch screen emits a touch screen signal.

[0016] When the controller receives the touch screen signal emitted by the touch screen, it detects the position coordinate information in the touch screen signal.

[0017] If the position coordinate information is abnormal, a timer is started, and the position coordinate information is continuously detected within a set time.

[0018] If it is detected again that the position coordinate information is still abnormal within the set time, the touch screen is reset and restarted through the reset control line and the diode.

[0019] Preferably, the touch screen signal includes: position information, interrupt response signal, and reset signal.

[0020] Preferably, when a touch occurs, the INT pin of the touch screen emits an interrupt response signal, and at the same time, the SDA pin and SCL pin of the touch screen emit position information, which is transmitted to the controller through the SDA data line and the SCL clock line.

[0021] Preferably, detecting the position coordinate information includes:

[0022] When the INT pin of the controller receives the interrupt response signal emitted by the touch screen, it detects whether the position coordinate information in the data received by the SDA pin is 0. If it is not 0, the position coordinate information is normal; if it is 0, the position coordinate information is temporarily considered abnormal.

[0023] Preferably, after the timer is started, if an interrupt response signal is received within the set time, it indicates that a touch has occurred. Then it is detected again whether the position coordinate information is 0. If it is not 0, it means the position coordinate information is normal, and the timer is cleared.

[0024] Preferably, if the position coordinate information detected again is still 0, it is considered a real data anomaly, the timer is cleared, and the chip reset program is started.

[0025] Preferably, the controller's RST pin issues a reset signal, and the SDA pin is forced to pull low through a diode to reset and restart the internal chip of the touch screen.

[0026] Compared with the prior art, the beneficial effects of the present invention at least include: judging anomalies through control software and then resetting the chip, and cooperating with the improvement of the touch screen control circuit, which can effectively reduce the occurrence of the touch screen not working caused by electromagnetic interference, and can effectively resist the electrostatic discharge test of 10KV for contact discharge and 15KV for air discharge. The screen does not go black, and the touch failure can be restored within 2 - 3 seconds. Description of the Drawings

[0027] Figure 1 is a schematic diagram of the circuit of the present invention. Detailed Embodiments

[0028] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the spirit of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0029] As Figure 1 shown, Embodiment 1 of the present invention provides an anti-interference circuit for a touch screen, including:

[0030] The touch screen is connected to the controller through a communication line. Specifically, the SDA pin of the touch screen is connected to the SDA pin of the controller through the SDA data line, the SCL pin of the touch screen is connected to the SCL pin of the controller through the SCL clock line, the INT pin of the touch screen is connected to the INT pin of the controller, and the RST pin of the touch screen is connected to the RST pin of the controller through a reset control line. The SDA data line and the reset control line are connected through a diode.

[0031] The controller is used to receive touch screen signals and reset and restart the interfered touch screen when data anomalies are detected.

[0032] Adding a diode to SDA and RST, and then cooperating with the method of resetting the RST pin can effectively improve the anti-interference ability of the touch screen.

[0033] Embodiment 2 of the present invention provides a method for anti-electromagnetic interference of a touch screen, based on the anti-electromagnetic interference circuit of the touch screen described in Embodiment 1, including:

[0034] The touch screen signals include: position information, interrupt response signal, and reset signal. The position information is transmitted by the I2C bus: two signal lines, SDA and SCL, where SDA is the data line and SCL is the clock line. The interrupt response signal: INT. The reset signal: RST.

[0035] Under strong electromagnetic interference, the I2C bus may malfunction or stop working. The phenomenon is that the controller can receive the interrupt response signal, but there is no SDA data.

[0036] 1) When the touch screen is touched, the SDA and SCL pins of the touch screen send out position information, which is transmitted to the controller through the SDA data line and the SCL clock line. The INT pin of the touch screen sends out the interrupt response signal. When the INT pin of the controller receives the interrupt response signal sent by the touch screen, it detects whether there is an abnormality in the position coordinate information in the SDA data, that is, checks whether the position coordinate information is "0". If it is not "0", the data is normal; if it is "0", the data is temporarily considered abnormal.

[0037] 2) When the data is abnormal, start the timer. If an interrupt response signal is received within the set time, it means that a touch has occurred, and execute according to step 1. If the current data is not "0", clear the timer. If it is still "0", it is considered a true data abnormality. Similarly, clear the timer and start the chip reset program. The controller's RST pin gives a reset signal. When the RST gives a reset signal, that is, when the signal level is 0, the SDA pin is forced to be pulled low through a diode, so that the internal chip of the touch screen resets and restarts. After the touch screen data abnormality disappears, return to step 1. In the present invention, the set time is 5s.

[0038] When there is an interrupt response signal but the position coordinate information in the SDA data cannot be detected, it indicates that the I2C bus is severely interfered. Reset the touch screen touch chip to restore the chip to its initial state so that it can work normally again. Through the above steps, the occurrence of the situation where the touch screen does not work caused by electromagnetic interference can be effectively reduced, and an ideal state can be achieved through cooperation with improvements in the circuit.

[0039] As one of the prominent substantive features of the present invention and a significant improvement over the prior art, the present invention realizes anti-interference of the touch screen through the cooperation of control software and circuit improvement. On the basis of a simpler circuit structure, the anti-interference effect is achieved, with low cost and good effect.

[0040] Embodiment 3 of the present invention provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the computer program is loaded into the processor, it implements a method for anti-electromagnetic interference of a touch screen according to Embodiment 2.

[0041] Embodiment 4 of the present invention provides a computer-readable storage medium storing a computer program, which when executed by a processor implements the method for anti-electromagnetic interference of a touch screen according to Embodiment 2.

[0042] The present disclosure may be a system, a method, and / or a computer program product. The computer program product may include a computer-readable storage medium having thereon computer-readable program instructions for causing a processor to implement various aspects of the present disclosure.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications or equivalent replacements can still be made to the specific embodiments of the present invention, and any modifications or equivalent replacements without departing from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A hardware circuit for anti-electromagnetic interference of a touch screen, characterized in that, Including: A touch screen, a controller, and a diode; The touch screen and the controller are connected through a communication line, and the communication line includes an SDA data line and a reset control line; The SDA data line and the reset control line are connected through a diode; The controller is used to receive touch screen signals. When data anomalies are detected, the touch screen that has been interfered is reset and restarted through the diode; Among them, the SDA pin of the touch screen is connected to the SDA pin of the controller through the SDA data line, and the SCL pin of the touch screen is connected to the SCL pin of the controller through the SCL clock line; the INT pin of the touch screen is connected to the INT pin of the controller, and the RST pin of the touch screen is connected to the RST pin of the controller through the reset control line; the positive pole of the diode is connected to the SDA data line, and the negative pole of the diode is connected to the reset control line; when the controller detects that the position coordinates in the data output by the SDA pin of the touch screen are abnormal, the RST pin of the controller outputs a reset signal with a level of 0, and the touch screen that has been interfered is reset and restarted through the diode.

2. A hardware circuit control method for anti-electromagnetic interference of a touch screen, based on the hardware circuit for anti-electromagnetic interference of a touch screen described in claim 1, characterized in that, Including: When a touch occurs, the touch screen emits a touch screen signal; When the controller receives the touch screen signal emitted by the touch screen, it detects the position coordinate information in the touch screen signal; If the position coordinate information is abnormal, a timer is started, and the position coordinate information is continuously detected within a set time; If the position coordinate information is detected to be abnormal again within the set time, the controller resets and restarts the touch screen through the reset control line and the diode.

3. The hardware circuit control method for anti-electromagnetic interference of a touch screen according to claim 2, wherein: The touch screen signal includes: position coordinate information, an interrupt response signal, and a reset signal.

4. The hardware circuit control method for anti-electromagnetic interference of a touch screen according to claim 2, wherein: When a touch occurs, the INT pin of the touch screen emits an interrupt response signal, and at the same time, the SDA pin and the SCL pin of the touch screen emit position coordinate information, which is transmitted to the controller through the SDA data line and the SCL clock line.

5. The hardware circuit control method for anti-electromagnetic interference of a touch screen according to claim 2, wherein: Detecting the position coordinate information includes: When the INT pin of the controller receives the interrupt response signal emitted by the touch screen, it detects whether the position coordinate information in the data received by the SDA pin is 0. If it is not 0, the position coordinate information is normal. If it is 0, the position coordinate information is temporarily considered abnormal, and a timer is started.

6. The hardware circuit control method for anti-electromagnetic interference of a touch screen according to claim 2, wherein: After the timer is started, if an interrupt response signal is received within the set time, it indicates that a touch has occurred. The position coordinate information is detected again to see if it is 0. If it is not 0, it means the position coordinate information is normal, and the timer is cleared.

7. The hardware circuit control method for anti-electromagnetic interference of a touch screen according to claim 6, wherein: If the position coordinate information detected again is still 0, it is determined that the position coordinate information is abnormal, the timer is cleared, and the chip reset program is started.

8. A hardware circuit control method for anti-electromagnetic interference of a touch screen, as described in claim 7, wherein: The controller sends a reset signal from the RST pin, which is transmitted to the touch screen through the reset control line, and the SDA pin is forced to be pulled low through a diode to reset and restart the internal chip of the touch screen.

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