SunFounder 2 Channel DC 5V Relay Module with Optocoupler Low Level Trigger Expansion Board Compatible with Arduino R3 MEGA 2560 1280 DSP ARM PIC AVR STM32 Raspberry Pi

bit late to the party, but I was successful by using a 5v USB-A port on the back of my projector. You can see it work on my most recent post. The parts needed: Spare (or current) wireless screen remote and USB cable (you'll cut the device end off and just use the USB-B as the power source. If it has white and green wires, you won't use them. You only need red and black) 2-channel 5v relay - https://a.co/d/0cOenbts Arduino board (I went with the Arduino Uno R3) - https://a.co/d/0fV5FO2t <or> you can go with a cheaper board that's Arduino compatible https://a.co/d/0gZGcNnD (comes with USB-B USB-B cable for the Arduino, no needed if you go with a cheaper board with the cable included Some wire and jumpers for connections (wire- https://a.co/d/0dxIo7MN) (breadboard/jumpers- https://a.co/d/08P0NXnN) It will require some coding, but it's nothing AI can't help you with. Tell AI you need an Arduino sketch for the following: ``` I need an Arduino Sketch to automate the projector screen power from a 5v USB trigger on the back of my projector. Here's how it should work using an Arduino UNO R3: Arduino watches pin 2 for voltage: 5V present = projector ON 0V = projector OFF It remembers the last projector state and compares it to the current state in each loop. When the projector turns ON: OFF>ON transition is detected Arduino pulses relay pin 8 This simulates pressing the screen DOWN button When the projector turns OFF: ON>OFF transition is detected Arduino pulses relay pin 9 This simulates pressing the screen UP button The relay module is active LOW: LOW = relay ON HIGH = relay OFF The pulseRelay() function: Turns the relay ON for 500 milliseconds Then turns it back OFF This creates a momentary button press instead of holding it A 3 second delay is included after each action to avoid double-triggering. Serial monitor output is included for debugging and status updates. In short: Projector ON = screen down Projector OFF = screen up ```