• PCA9685 PWM Board Bring Up Jun 28, 2021 - 8 min read The RoboCar I’m building needs to be able to control its steering servo and motor controller which both are driven by a PWM signal. Unfortunately single board computers (SBC) use a 40-pin GPIO, which only has one PWM output. The RockPi 4C board I am using cannot drive both. The solution to this is an I2C 16 channel PWM board called the PCA9685. These can be bought inexpensively, and while they are advertised for LEDs they can drive other things.