Multiple Inputs for a Motor

[heya101]

So our team wanted a backup system for our shooter which would be controlled by the throttle(knob) on the joystick. I can wire this up fine, but I'm wondering how I'd incorporate the code for when I want the shooter to set its speed automatically by the distance, since the motors would then receive two conflicting inputs.

Say the throttle is set at 0 speed, but I press the button for the automatic shooting, saying we need about .5 speed to get in the basket, how would I have the code make this override the throttle input?