To take Al's point further; Have you ruled out a power supply issue to the DSC?
If you are getting mixed results through swaptronics it is time to perform a more focused assessment of the problem.
I would take a serious look at how the problem is reproduced, isolate the components instead of focusing on the system as a whole. Take a single motor controller and pair it with a DSC, PD and Cable on a bench off of the robot. Make every attempt to reproduce the issue. Paying very close attention to the steps being followed and what action cause the erroneous behavior.
Once you are able to deterministic-ally reproduce the problem, then and only then will you be able to take the necessary steps to solving it.
Having said that, if the problem is intermittent finding how to reproduce it can be very difficult. But it is still important to attempt to due so and avoid creation of causal relationships that may not have anything to do with the actual problem.
Break the problem down to it's basic elements. From a hardware standpoint:
What needs to happen for me to make a motor move?
- Motor controller and DSC must have proper power.
- Motor controller must receive a constant, uninterrupted(<100ms) PWM signal
- Digital module on cRIO must be able to provide and uninterrupted non intermittent signal to the DSC.
You must also be able to rule out specific components such as the motor controller itself. The easiest way to do this is provide the PWM signal to the Talon using a secondary form of communication such as a VEX controller or a simple PWM generator or an RC hobby controller. Once you have ruled out the MC, you need to move on to the other components such as the DSC.
Testing the DSC is a little more difficult and requires you to know a little about how it works. But there is a simple test that you can do. If the problem is the DSC it is possible that it is only with one or two channels, try switching the PWM signal to a different channel. Remember that there is a separate driver IC for PWM channels 9 and 10 than there is for 1-8
http://www.usfirst.org/uploadedFiles...matic%20v7.pdf. Sometimes this IC fails or has intermittent issues that could be the cause of your problem.
All of these tests requisite that you are able to reproduce the problem. If you cannot reproduce the problem then you have no way to validate your corrective measures.
Now there is always the possibility that your problem is software. Try loading the default code and performing a simple PWM assignment from a joystick to a PWM channel. Try reproducing the issue on every channel. Compare these results against the actions taken to reproduce the problem.
Following a methodical and step by step approach is the only way you are going to be able to pinpoint the problem and say with any reasonable degree of certainty that you have fixed it.