like a throtle
FYI- it's called a speed control. (or motor speed control) At least half of all the ones sold on the web are pot controlled and do not provide uC interface pins because the target market for those is people with NO uController knowledge whatsoever, and just want
a knob they can turn to control the speed. This is even more true for speed controls above the power levels of the ones sold at Sparkfun and Adafruit. I have found higher wattage drivers with pwm interface connectors but the simple pot controlled ones are more prevalent. The Map function should work for you.