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Unread 30-01-2015, 14:45
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Re: Talon SRX CAN Daisy-Chain Wiring

Quote:
Originally Posted by timytamy View Post
Is that a typo? The PDP manual states it has a 120 ohm terminator resistor (selectable via jumper). If it is indeed a 50 ohm bus, I'd be very interested in reading more about it?
Two terminating resistors 120 ohm each in parallel = 60 ohm The spec has varying values for the terminating resistors depending on the exact situation.

In answer to Dan's question. The termination resistors are suppose to be on the end to kill reflections. Canbus is actually very forgiving. We have one robot that has been missing one of its termination resistors for a couple of years. It is one of our primary demo bots & it has been working fine. BUT when I am troubleshooting issues, one of the first things I do (after making sure it is plugged in) is make sure everything is done according to specification. So if I was having comms problems, I would make sure the wiring is correct, termination resistors are place, value, & quantity. And then go beat on the programers. (and eat their corn dogs.)

Sorry for the me too
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Last edited by FrankJ : 30-01-2015 at 14:46. Reason: I need to learn to type faster