Help Requested - "Fatal Task-Level Kernel Exception"

[Mike Betts]

Travis,

Is the motor a 775?

Mike

[Travis Hoffman]

Originally Posted by Mike Betts

Travis,

Is the motor a 775?

Mike

RS-550, freshly installed.

This motor was tested fine, on robot, just prior to this anomaly and worked swimmingly. It still moves in the upward direction really fast whenever I move the stick anywhere north of neutral. The Vic seems to just output max voltage regardless of input. When I move the stick down, even though the variable in the code is changing per NetConsole, there is no movement out of the arm, but the Vic clicks real fast. If the pump is running, it stutters to the same beat as the clicking. Thing is, I can still drive while the clicking is going on - drive motors are not seemingly affected.

I can't see the digital sidecar being the issue - all other outputs and inputs are working fine, and the problem moved to PWM8 when I moved the cable and changed the code.

I will say that right before the problem occurred, I changed one constant in the code and redownloaded, then poof. I do not know if this is a coincidence or code-related. I won't rule out this problem being code related

Is it possible for the WPILib source code C++ stuff I can't change to be corrupted, while my custom code is still good?

Maybe I'll reinstall the latest WPILib update and do a clean recompile.

At this point, I'm completely stumped.

[Mike Betts]

Travis,

You might want to focus on the compressor. When it is intermittent, is the DSC LED for that relay channel steady or intermittent? If the former, then software is probably not at fault. If the latter, then the DSC is being commanded to intermittently run the compressor by the CRIO and software is highly suspected.

If the above indicates software is OK, you might want to temporarily disconnect the spike to the compressor. Does the 550 operate smoothly? If so, you may have a circular path somehow in your frame...

Good Luck,

Mike

[Matt Krass]

When you swapped out the Jaguar for the Victor, did you change the code? The Jaguar PWMs update faster and might be causing the Victor to trip over itself trying to keep up.

[Travis Hoffman]

Originally Posted by Matt Krass

When you swapped out the Jaguar for the Victor, did you change the code? The Jaguar PWMs update faster and might be causing the Victor to trip over itself trying to keep up.

Sorry I didn't respond sooner to you guys - I was very busy all day prepping for Pittsburgh.

Yes, I changed the code when I switched the controller. It turns out the problem was tracked to a bad 10 AWG zip cord power cable running to the controller.

I am not a fan of large-gauge zip cord (red/black wires joined together into a single cord). It is far too easy to tear the insulation during lead separation and expose the copper in those things. There was a small tear in both of them that was causing an intermittent short. I swapped out the cable to independent red and black wires, and the problem disappeared. I enjoyed hacking the zip cord into little pieces before disposing of it!

For smaller gauges like 18, zip cord is great - the two wires readily separate. For large gauges, I'm going with indivdual wires from now on.

Thanks to all who suggested ideas.