I want to share three new articles I wrote discussing what is Pulse Width Modulation (PWM) and how to use it on the Raspberry Pi using two Node.js libraries: RPIO and PIGPIO.
Pulse Width Modulation (PWM) is an interesting concept that allows you to control an analog circuit (a LED on the project that is discussed in the articles) via a digital signal.
The first article (Pulse-Width Modulation (PWM) — Theory) explains how this really cool concept works. The second article is an implementation of the theory using Hardware-based PWM with RPIO by using a Node.js library called RPIO. The third article uses another Node.js library called PIGPIO to control the same circuit but using Software-based PWM with PIGPIO.
So what’s the difference? Great question, I am glad you asked. One of them allows you to use more pins on the Raspberry Pi, but I am not going to tell you which one… You have to read it in the articles I wrote ;-)
P.S. Sorry to make you go to my site, rather than posting the information here, but formating the information here is difficult.