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Unread 20-03-2011, 15:05
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FRC #0358 (Robotic Eagles)
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Re: Weirdest problem in autonomous mode.

Safety Config Tutorial.pdf

It's just like the Watchdog in concept, but now hidden within specific LabVIEW FRC palette vi's. I'm also not sure it enhances safety, since if you don't understand what it's doing, then it'll probably get bypassed in an equally unsafe manner.

It's only implemented in the drive base Open 2/4 Motor vi's and subsequent uses of Tank/Arcade/Holonomic/Motors drive tied to that motor reference will feed the timer. It is not implemented in individual motor opens, such as for arm control.

The safety timer defaults to .1 second. If a call isn't made to Tank/Arcade/Holonomic/Motors with the timeout period, then the associated PWM outputs are set to zero.

It is easy to disable.
Simply double-click on the Open 2/4 Motor vi's you use in Begin.vi and you'll see "enable" right in the middle of the associated block diagram.
Just set it to "disable" to turn it off.

The concept behind the Safety Vi's is that during debugging/breakpointing or due to overly slow to respond code, the motors automatically get shut down, to keep the robot from running rampant.

It has the unfortunate consequence of invalidating a (what I consider a more efficient) style of programming and clutters up teaching basic programming concepts.
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Last edited by Mark McLeod : 20-03-2011 at 15:09.
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