Thread: CAN Jaguar: could longer CAN cables cause problems?
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Unread 31-01-2014, 08:56
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Al Skierkiewicz Al Skierkiewicz is offline
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Re: CAN Jaguar: could longer CAN cables cause problems?
About 90% of all CAN issues I have seen are traceable to the termination loads. Remember that the wiring is a transmission line just like coax to an antenna. Without the correct loading, there are a lot of reflections of signal along the line. The CAN bus requires a termination at both ends of the line so if you made your own RS232 interface, this requires a resistor as well. The termination resistor is 100 ohms. Using something other than 100 ohms is almost as bad as no termination. The flat cable that the phone company uses in lengths of 20 feet or less, emulate a twisted pair transmission line at 1MHz just fine. Yes, it is not hard to make your own RJ11 plugs but you can screw it up too. Just be careful and follow the instructions. The Jaguar Getting Started Guide on the FIRST website or IFI site has some great instructions in Chapter 6.
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www.wildstang.org
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Last edited by Al Skierkiewicz : 31-01-2014 at 09:01.