RS485 communication terminal resistance connection circuit

Abstract

The utility model discloses a kind of RS485 communication terminal resistance connecting circuit, including controller installed on stage lamp, RS485 conversion chip and resistance switching chip;The controller sends RS485 protocol signal to RS485 conversion chip by RS485 serial port;RS485 data is sent to stage lamp by the output end of RS485 conversion chip, then address code is returned to controller by stage lamp, after controller receives the address code of tail stage lamp, drive signal is sent to resistance switching chip, resistance switching chip works, and the output end of RS485 conversion chip is short-circuited by preventing signal distortion resistance by output end after work, to improve the safety of stage lamp operation, avoid the case of misplug or missplug terminal plug, simultaneously also reduced the cost of using people.

Description

Technical Field

[0001] This utility model relates to the field of RS485 communication circuits for stage lights, and in particular to an RS485 communication terminal resistor connection circuit. Background Technology

[0002] Currently, in the control and use of stage lighting, to prevent signal transmission distortion from causing malfunctions in lights located far from the control console when controlling multiple stage lights over long distances, such as... Figure 1 and Figure 2 As shown, existing technology generally uses a shielded twisted-pair signal cable to connect the controller's DMX output port to the DMX input port of the first device, and from the first device's DMX output port to the second device's DMX input port, and so on, until all the lights are connected. Then, a terminating plug with a 120R resistor is installed on the last connected light in each circuit to prevent signal distortion. However, this solution requires manual soldering and installation of the terminating plug with the terminating resistor. In large performance venues with a large number of lights and multiple connection paths, the probability of mis-plugging or missing terminating plugs increases. Moreover, since some lights may be installed at height, even if the error is discovered, it is difficult to reinstall the terminating plug, increasing labor costs and reducing safety. Utility Model Content

[0003] The purpose of this invention is to provide an RS485 communication terminal resistor connection circuit that can improve the safety of stage lighting operation.

[0004] The RS485 communication terminal resistor connection circuit of this utility model includes a controller installed on a stage light, an RS485 conversion chip, and a resistor switching chip. The controller sends RS485 protocol signals to the RS485 conversion chip through an RS485 serial port. The output of the RS485 conversion chip sends RS485 data to the stage light, and then the stage light returns an address code to the controller. After receiving the address code of the tail stage light, the controller sends a drive signal to the resistor switching chip. After the resistor switching chip is working, its output is short-circuited by an anti-signal distortion resistor.

[0005] In a preferred embodiment of this utility model, the RS485 serial port output terminal of the controller is electrically connected to the input terminal of the RS485 conversion chip; the drive output terminal of the controller is electrically connected to the input terminal of the resistor switching chip; and the feedback input terminal of the controller is electrically connected to the stage light.

[0006] As a preferred embodiment of this utility model, the R pin (USART1RX) and D pin (USART1TX) of the input terminal of the RS485 converter chip are electrically connected to the RX pin (USART1RX) and TX pin (USART1TX) of the RS485 serial port of the controller, respectively. The RE pin and DE pin of the input terminal of the RS485 converter chip are both electrically connected to the control terminal RS4852 of the RS485 serial port of the controller. The A pin and B pin of the output terminal of the RS485 converter chip are electrically connected to the stage light. The A pin and B pin of the output terminal of the RS485 converter chip are also electrically connected to the output terminal of the resistance switching chip through an anti-signal distortion resistor.

[0007] In a preferred embodiment of this utility model, the resistor switching chip is an optocoupler resistor switching chip. The internal input terminal of the optocoupler resistor switching chip is provided with a light-emitting diode. The anode of the light-emitting diode is connected to the power supply, and the cathode is electrically connected to the driving terminal of the controller. The internal output terminal of the optocoupler resistor switching chip is provided with a photoelectric switch. The A+ terminal of the photoelectric switch is electrically connected to the A pin of the output terminal of the RS485 conversion chip, and the B+ terminal of the photoelectric switch is electrically connected to the B pin of the output terminal of the RS485 conversion chip through an anti-signal distortion resistor.

[0008] As a preferred embodiment of this utility model, the cathode side of the optocoupler resistor switching chip is electrically connected to the drive end of the controller through a first current-limiting resistor.

[0009] As a preferred embodiment of this utility model, pin A of the output terminal of the RS485 conversion chip is electrically connected to the power supply through a second current-limiting resistor.

[0010] As a preferred embodiment of this utility model, pin B of the output terminal of the RS485 conversion chip is connected to ground through a grounding resistor.

[0011] As a preferred embodiment of this utility model, the resistance value of the anti-signal distortion resistor is 120Ω.

[0012] The RS485 communication terminal resistor connection circuit described in this utility model improves the safety of stage light operation by using a controller, an RS485 conversion chip, and a resistor switching chip on the stage light. After receiving the address code of the tail stage light, the controller sends a drive signal to the resistor switching chip, which then short-circuits the output terminal of the RS485 conversion chip through an anti-signal distortion resistor. This avoids mis-plugging or missing terminal plugs and also reduces labor costs. Attached Figure Description

[0013] Figure 1 A schematic diagram illustrating the use of a single shielded twisted-pair signal cable to connect all stage lights in the existing technology;

[0014] Figure 2A schematic diagram of an existing technology plug with a 120R resistor terminal;

[0015] Figure 3 This is a schematic diagram of the RS485 communication terminal resistor connection circuit of this utility model;

[0016] Figure 4 This is the circuit diagram for the controller;

[0017] Figure 5 This is the circuit diagram of the RS485 converter chip.

[0018] Figure 6 This is the circuit diagram of a resistor switching chip. Detailed Implementation

[0019] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0020] This embodiment provides an RS485 communication terminal resistor connection circuit, such as... Figure 3 As shown, the system includes a controller U1 mounted on a stage light, an RS485 conversion chip U2, and a resistor switching chip U3. The controller U1 sends RS485 protocol signals to the RS485 conversion chip via an RS485 serial port. The output of the RS485 conversion chip sends RS485 data to the stage light, and then the stage light returns an address code to the controller. After receiving the address code of the tail stage light, the controller sends a drive signal to the resistor switching chip. After the resistor switching chip is activated, its output is shorted by the anti-signal distortion resistor R4.

[0021] The 120R anti-signal distortion resistor can prevent RS485 signal distortion. The output terminal of the RS485 conversion chip is shorted by the resistor switching chip through the 120R anti-signal distortion resistor, which can improve the safety of stage light operation, avoid the situation of misplugging or missing terminal plugs, and also reduce labor costs.

[0022] like Figure 4 As shown, the RS485 serial port output of controller U1 is electrically connected to the input of RS485 conversion chip U2; the drive output of the controller is electrically connected to the input of resistor switching chip U3; and the feedback input of the controller is electrically connected to the stage light. Controller U1 can be an STM32 series microcontroller chip.

[0023] like Figure 5As shown, the R pin (USART1 RX) and D pin (USART1 TX) of the RS485 converter chip are electrically connected to the RX pin (USART1 RX) and TX pin (USART1 TX) of the controller's RS485 serial port, respectively. The RE pin and DE pin of the RS485 converter chip are both electrically connected to the control terminal RS4852 of the controller's RS485 serial port. The A pin and B pin of the RS485 converter chip are electrically connected to the stage light. The A pin and B pin of the RS485 converter chip are also electrically connected to the output of a resistance switching chip through an anti-signal distortion resistor. The RS485 converter chip used is the SP3485 chip. A filter capacitor C1 is also connected between the VCC and GND terminals of the RS485 converter chip.

[0024] The A pin of the RS485 converter chip's output terminal is electrically connected to the power supply through a second current-limiting resistor R1, which avoids the influence of the 3.3V power supply and thus improves the stability of the RS485 converter chip's output signal. Additionally, the B pin of the RS485 converter chip's output terminal is connected to ground through a grounding resistor R2, which also improves the stability of the RS485 converter chip's output signal.

[0025] like Figure 6 As shown, the resistor switching chip is an optocoupler resistor switching chip. The internal input terminal of the optocoupler resistor switching chip is equipped with a light-emitting diode. The anode of the light-emitting diode is connected to a 3.3V power supply, and the cathode is electrically connected to the drive terminal DMX-RL of the controller. The internal output terminal of the optocoupler resistor switching chip is equipped with a photoelectric switch. The A+ terminal of the photoelectric switch is electrically connected to the A pin of the output terminal of the RS485 conversion chip, and the B+ terminal of the photoelectric switch is electrically connected to the B pin of the output terminal of the RS485 conversion chip through an anti-signal distortion resistor.

[0026] When the controller does not receive the address code from the tail stage light, it sends a high-level signal to the cathode of the LED inside the resistor switching chip via the DMX-RL pin of the driver terminal. At this time, the LED is not working, so the A+ and B+ terminals of the photoelectric switch in the resistor switching chip are not connected. Therefore, the anti-signal distortion resistor R4 will not short-circuit the A and B pins of the RS485 conversion chip's output. When the controller receives the address code from the tail stage light, it sends a low-level signal to the cathode of the LED inside the resistor switching chip via the DMX-RL pin of the driver terminal. At this time, the LED is working, so the A+ and B+ terminals of the photoelectric switch in the resistor switching chip are connected. The anti-signal distortion resistor R4 short-circuits the A and B pins of the RS485 conversion chip's output, preventing RS485 signal distortion. This improves the safety of stage light operation, avoids mis-plugging or missing terminal plugs, and also reduces labor costs. In addition, the cathode of the optocoupler resistor switching chip is electrically connected to the DMX-RL pin of the controller via the first current-limiting resistor R3. The first current-limiting resistor R3 can protect the resistor switching chip.

[0027] The above embodiments are only used to illustrate the detailed solution of this utility model. This utility model is not limited to the above detailed solution, that is, it does not mean that this utility model must rely on the above detailed solution to be implemented. Those skilled in the art should understand that any improvement to this utility model, equivalent substitution of the raw materials of this utility model product, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of this utility model.

Claims

1. An RS485 communication terminal resistor connection circuit, characterized in that, The system includes a controller (U1) installed on the stage lights, an RS485 conversion chip (U2), and a resistor switching chip (U3). The controller (U1) sends RS485 protocol signals to the RS485 conversion chip via an RS485 serial port. The output of the RS485 conversion chip sends RS485 data to the stage lights, and then the stage lights return an address code to the controller. After receiving the address code of the tail stage lights, the controller sends a drive signal to the resistor switching chip. After the resistor switching chip is activated, its output is shorted by an anti-signal distortion resistor (R4) to the output of the RS485 conversion chip.

2. The RS485 communication terminal resistor connection circuit according to claim 1, characterized in that, The RS485 serial port output of the controller (U1) is electrically connected to the input of the RS485 conversion chip (U2); the drive output of the controller is electrically connected to the input of the resistor switching chip (U3); and the feedback input of the controller is electrically connected to the stage light.

3. The RS485 communication terminal resistor connection circuit according to claim 2, characterized in that, The R and D pins of the input terminal of the RS485 converter chip are electrically connected to the RX and TX pins of the RS485 serial port of the controller, respectively. The RE and DE pins of the input terminal of the RS485 converter chip are electrically connected to the control terminal of the RS485 serial port of the controller. The A and B pins of the output terminal of the RS485 converter chip are electrically connected to the stage light. The A and B pins of the output terminal of the RS485 converter chip are also electrically connected to the output terminal of the resistor switching chip through the anti-signal distortion resistor.

4. The RS485 communication terminal resistor connection circuit according to claim 3, characterized in that, The resistor switching chip is an optocoupler resistor switching chip. The internal input terminal of the optocoupler resistor switching chip is equipped with a light-emitting diode. The anode of the light-emitting diode is connected to the power supply, and the cathode is electrically connected to the driving terminal of the controller. The internal output terminal of the optocoupler resistor switching chip is equipped with a photoelectric switch. The A+ terminal of the photoelectric switch is electrically connected to the A pin of the output terminal of the RS485 conversion chip, and the B+ terminal of the photoelectric switch is electrically connected to the B pin of the output terminal of the RS485 conversion chip through an anti-signal distortion resistor.

5. The RS485 communication terminal resistor connection circuit according to claim 4, characterized in that, The cathode of the optocoupler resistor switching chip is electrically connected to the drive terminal of the controller through the first current-limiting resistor (R3).

6. The RS485 communication terminal resistor connection circuit according to claim 3, characterized in that, The A pin of the RS485 converter chip's output terminal is electrically connected to the power supply through the second current-limiting resistor (R1).

7. The RS485 communication terminal resistor connection circuit according to claim 3, characterized in that, The B pin of the RS485 converter chip's output terminal is connected to ground via a grounding resistor (R2).

8. The RS485 communication terminal resistor connection circuit according to any one of claims 1-7, characterized in that, The resistance of the anti-signal distortion resistor is 120Ω.

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