It requires two pins to control the direction and one pulse width modulation (PWM) pin to control the speed. The pins are passed via constructor and the names should be self-explanatory.

[Runtimemicro] has the answer, at least if you are writing PWM code for the Arduino. Their free application lets you set a few parameters, visually see the results, and then generates code for you.

In this tutorial, T.K. Hareendran shows us how to set up an interleaved PWM output on an Arduino Uno. He then uses different techniques to validate that the desired result is achieve.