Using PWM plus a RESTful API to set colors for an RGB LED

Now, we will use the same source code to make it possible to change the color of an RGB LED, specifically, a common cathode RGB LED. This electronic component provides a common cathode and three anodes, that is, an anode for each of the three colors: red, green and blue. We can use our code to pulse width modulate the three colors and make the LED produce the mixed colors. We don't need to use a black surface to see the intersection of the three colors because the RGB LED mixes the three colors for us.

The following image shows a common cathode RGB LED with one of the most common configurations for the pins, where the common cathode is the second pin and the longest one.

The following table shows the pin configuration for the previous RGB LED, from left to right. However, always make sure that you check the datasheet for your RGB LED to check the right pins for the common cathode and the anode for each color.

Pin number	Description...