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Unread 03-02-2012, 14:56
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FRC #0492 (Titan Robotics)
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CAN Jaguar losing power temporarily

I have read a thread somewhere that if the motor gets stalled, it could draw down the voltage such that the Jaguar may get reset or power cycled. The thread has a concern that the Jaguar may lose it's configuration (e.g. Encoder lines, mode, coast vs brake etc.) such that the Jag will no longer respond to Set() or does not behave correctly as a result. We haven't hit this but is this a real concern? Because if it is, we will revise our code to anticipate and recover from it. For example, I assume we can call GetPowerCycled() to determine if the Jag has lost power temporarily and can "reinitialize" all the Jag parameters. We can do this before every Set() call.

If this is a real concern, ideally, the CANJaguar module should recover from it automatically. It's a lot easier to do it there (may be for next year?). If we have to do it ourselves, we would define a new CANJag class that will inherit CANJaguar so we can keep track of (shadow) all the Jag parameters. And we will override Set such that we will check for power loss and reconfigure the jag before setting the motor output.
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