The control of the RGB led is made with PWM(Pulse With Modulation), because PIC18F25K20 only have 2 PWM outputs (Hardware), I did the PWM by software to have 3 PWM outputs for that I use TIMER0 and for the Manual mode I use IOC(interrupt on change).

In this project I use push buttons to change between modes and to change the colors. But if we use the button as in the circuit (1) we have a problem. The problem with this configuration, due to the mechanical nature of any switch that may contains spring return action of some kind, there won’t be a clean transition from a state to another, but instead there will be a series of high and low states spikes. To solve that problem we have to implement a de-bouncing system, it can be done by hardware or software. We can use a RC delay circuit or it can be done with a schmitt trigger, but both ways will increase the price. So I done by software the de-bounce.

Example of code to do de-bounce: