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Unread 04-04-2011, 13:17
John Heden John Heden is offline
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Re: Unexplained intermittent CAN / 2CAN Jaguar problems at GSR

Quote:
Originally Posted by taichichuan View Post
Routing CAN traffic through the radio could certainly cause problems. The radio's ports have a limited amount of buffer space before the 802.3x congestion control messages start flying around on the net. I'm not sure what the 2CAN would do if it suddenly started getting a lot of source quench message traffic. Certainly, packets would start getting lost and that would be bad on a half-duplex style network like CAN (at least in the way it's implemented for FIRST). So, it's probably better to wire the 2CAN to port 1 on the cRIO and wire the radio on the other port of the 2CAN.

My $.02,

Mike
Mike,

Thanks for your thoughts. We initially had the 2CAN device on the CRIO port 1 connector which is where we first started to see our problems. The buffer capacity of the 2CAN vs. the radio was unclear but our intuition gave the radio the advantage here. I believe our next step will be to simply move to port 2 of the CRIO and see whether that helps things.

Thanks,

John
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