An electronic Advent wreath with four "candles" based on the Arduino Uno.
The Arduino Uno Revision 3 is equipped with a prototyping shield with the following components:
| Arduino name | ATmega328P name | component |
|---|---|---|
| A0, D14 | PC0 | red push button |
| A1, D15 | PC1 | yellow push button |
| A2, D16 | PC2 | green push button |
| A3, D17 | PC3 | blue push button |
| D9 | PB1 (PWM OC1A) | red LED |
| D10 | PB2 (PWM OC1B) | yellow LED |
| D11 | PB3 (PWM OC2A) | green LED |
| D3 | PD3 (PWM OC2B) | blue LED |
The push buttons are normally open and connect to ground when pressed (inverted logic). Attention: The push buttons are not debounced.
The LEDs are sourced by the related output pins (normal logic). The selected pins can be used as an output of a Pulse Width Modulation (PWM) unit:
- The outputs OC1A and OC1B connect to a 16-bit PWM unit.
- The outputs OC2A and OC2B connect to a 8-bit PWM unit.
This application uses the Hardware Abstraction Layer by Rahix for the Atmel / Microchip AVR microcontrollers. For further information see avr-hal README.