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 ...