[airnate]

The Basic Robot Main.vi almost does what you want out of the box in Arcade drive. I would suggest hooking your single motor to one of the PWM channels, let's say PWM 1.

Prior to making any changes to the Basic Robot Main.vi you should be able to run it and control the motion using the joystick back and forth motion (ignore side to side for the time being).

So if you really would rather have the behavior that you describe, you may want to set it up like the attached image.