Thread: DS reliability
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Unread 07-07-2010, 22:49
Greg McKaskle Greg McKaskle is offline
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Re: DS reliability

Are you displaying the delta time between processed packets in RobotMain?

Like Joe, I'm curious what is running on the Classmate, perhaps what the power and wifi settings are.

I instrumented the code last year to get a sense of the latency and dropped packets, but the code was removed before shipping. The reason for the DS messages about watchdog counts was to detect and report short WD glitches since lost packets and/or latent packets will after enough time result in a system watchdog. This wasn't as informative as heavily instrumented framework, but allowed for the most obvious symptom of latent packets to be noticed and hopefully a cause and effect established.

You may also want to note the CPU usage of the Classmate and the DS mode. When in disabled mode, the DS does extra work to enumerate joysticks and detect changes, and if no estop button is present, it is also looking for the button. When enabled, these tasks no longer take place, and you should see an effect in the timings or in the CPU load. There is also a difference if the Cypress board is attached.

Please post with questions or observations.
Greg McKaskle
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