[tsaksa]

How are you controlling the robot during the tests? If you are using a driver station are you sure that is working correctly? Try this, change your code to have the joysticks on the drive station control two things. For example, when the right side of the drive train moves forward have the code output a PWM signal and turn on a spike or some other device that you can use to verify that the code is really getting commands. You can use this to verify that the code is really getting the right input and is executing the way you expect.

Once you verify that your driver station input is working, change the code to output multiple PWM signals, so that you can check for a bad digital sidecar. For example, lets say that the right side motor is connected to PWM 1 and the left side to PWM 2, have the code also output the right side to PWM 3, and the Left side to PWM 4. You can then swap PWM cables to more locations. If one PWM output works, but it pair does not you may have a bad DS or bad cable. If they are all bad you might have a software or driver station problem.

One area to check is the PWM cable and how it plugs into the motor controller. This connection can be flaky. To insure that you know for sure that a PWM signal is coming from the DS, plug a hobby servo into the questionable PWM port. You will need to add a jumper to the two pind next to that port to power a servo. If the servo responds but the controller does not, you know that the problem is not in the DS, code, or other wiring from the CRIO.

Again, make one change at a time, but trust nothing. Work back from the simplest configuration you can and test every component separately. Hobby servos are a great teat device for this type of PWM debugging.