Introduction: ATtiny Dark Detector
This little project makes an ATtiny tell you when it is dark or bright. This project is an excellent introduction to the capabilities of the ATtiny85 chip.
You can also see these instructions on my website www.PeterFoxFlick.com
Step 1: Parts
- Solderless Breadboard
- ATtiny 85
- Red Led
- Green Led
- 2 330 ohm Resistors
- 10k ohm Resistor
- Jumper Wires
- ATtiny Programer
Step 2: Build the Photocell Circuit
Build the photocell circuit. Connect one leg of the photocell to 5v. Connect the other leg to the digital 2 pin on the Arduino Uno and the 10k resistor. Connect the other leg of the resistor to ground.
Step 3: Serial Communication
Use the Arduino Uno and serial communication to read the level of light coming from your photocell. You will need to upload the code at the bottom of the page and then click on the Serial Monitor button (top right). Record a number that seems to be a good cut off for when you want your ATtiny to say it is dark.
Step 4: Upload Code to ATtiny
Upload this code to the ATtiny85. If you need help on how to do this follow this tutorial. Feel free to change the threshold to whatever number you decided on in STEP 2. I picked 600 because it worked where I was at the time of programming.
Step 5: Build the Circuit
Build the circuit for the ATtiny85 chip. Follow the images or the schematic in the program.