PWM Channels Not Responding?

[Team 4457]

Hey, so here is our problem:

We are using two talons to run a four motor drive train (we are sure that that is not the problem) and we are correctly wired and all the wires work. But when we go to run the robot, only one of the two PWM channels work (this was determined by swapping around cables). The joysticks both work. Does this mean that this is a programing issue? If so, do you have any idea what is could be?

Thank you,
Team 4457

[EricH]

Originally Posted by Team 4457

Hey, so here is our problem:

We are using two talons to run a four motor drive train (we are sure that that is not the problem)

Actually, I'm willing to bet that this is A problem. It might not be the one you're trying to solve, but there are very specific motors that can be run with more than one motor per speed controller, and most of the common drive motors do NOT fall into that category, especially CIMs. Take a good look at R52 and your drive motors' part numbers. (If you're using motors that are legal to run two to a speed controller... well, that's your decision, but those motors tend to be weaker than, say 4 CIMs through the KOP gearbox when used in drive.) Your regional's inspectors will almost certainly catch that one.

and we are correctly wired and all the wires work. But when we go to run the robot, only one of the two PWM channels work (this was determined by swapping around cables). The joysticks both work. Does this mean that this is a programing issue? If so, do you have any idea what is could be?

(See prior statement on legality of wiring two motors to one speed controller... but I digress.) You could just have a bad PWM cable. There could be other factors in play, however, so here are a couple of diagnostic questions for you.

What are the lights on the Digital Sidecar doing?
What is the light on the Talon doing on the channel that does not work?
What channels are you plugged into, and what channels is your code controlling with the joysticks? (Have you tried other channels to see if they work?)