In this tutorial, we will send the analog readings obtained from a Photo Resistor, also known as a Light Dependent Resistor (LDR), to the computer. We will display the each reading on the monitor using a simple Processing sketch.
Here is what you will need to complete the Arduino side of the project:
- PhotoCell (or PhotoResistor)
- 10K resistor
- Arduino UNO
- 3-4 wires(to connect it all together)
- USB cable to upload sketch and for Serial communication with Processing.
Arduino Sketch Explanation:
Here is a very basic Processing Sketch that will allow you to receive data from the Serial port attached to the Arduino and display the reading on your computer screen. In my case, the Arduino is connected to COM13. You may need to change this if you decide to follow in my footsteps.
The processing sketch will look for the line feed character ' \n' coming from COM13, which will trigger a serialEvent(). You can get processing to look for another character if you want to: just change the character within the bufferUntil() command. The draw() method is made redundant because the screen updating is handled by the serialEvent() in response to serial data communication with the Arduino UNO.