Just a quick post with an example sketch for how to setup timer 3 on an Arduino Yun to control the brightness of an LED. I had to go through figuring this out while experimenting with brightness and flash patterns. Anyway…. It’s just a simple sketch. I’m not really sure why a prescaler of 1 doesn’t work (I guess the LED switches on and off too quickly). I’m not going to explain the ins and outs of a PWM for LED control (there are lot of good examples on the web).