Ready, Set, Oscillate! The Fastest Way to Change Arduino Pins

There are many ways to change an output pin. The way we know and love is the famous digitalWrite() function. (Spoiler: Want a faster digitalWrite? Download Here!)

But even the Arduino Reference claims that it is not the most efficient. The Arduino functions do a lot of error checking to make sure the pin is configured right and has to map Arduino numbering to actual IO ports.  All this cost processor cycles, and time.  But how much? This article is not to teach you how to useIO registers, you can read about it on the Arduino Port Manipulation page. This is to cover exactly how inefficient the Arduino functions are.