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Re: Can Jaguars
Quote:
Originally Posted by FrankJ
Use terminating resistors. I not sure this is really needed in the short cable runs, but why tempt fate. Besides the first on the list of troubleshooting is to check the wiring.
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I've never seen a short CAN bus (the shortest I ever ran was ~3' with two nodes) work without a terminating resistor. I have seen short CAN busses work with only one 120ohm resistor somewhere on the bus instead of the spec'd one at each end, and I've also seen long busses with 1 60ohm resistor instead of 2 120ohm resistors.
I've also seen long busses with a 120ohm near one end and no other terminating resistor do really strange things with reflections (we had a node that was actually wired inverted and was reading the reflections instead of the actual message... that was weird)
Bottom line: You need both resistors for reliable performance. On a short enough bus, you can get away with just one.
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Last edited by apalrd : 08-11-2012 at 11:27.
Reason: Fixed terminating braket on quote
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