Blinking Christmas Tree

Purpose

Christmas is coming ... and if you need a last minute present, this electronic blinking christmas tree could help you.

Function

The circuit consists of a PIC16F84 and 12 LEDs which are driven by PWM. The low current LEDs should be connected to a 470 Ohm resistor.

The program uses a pseudo random number table to define the blinking intervals. Every LED that finishes a blinking cycle increases the table pointer. The timer counts with 500 Hz (prescaler 1:8), every ten steps the LED registers are decremented. The LEDs are dimmed on and off.

Circuit

Download

Eagle files and source code for a PIC16F84 blinking christmas tree. Released under GPL.