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Unread 26-01-2012, 23:04
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Re: CAN troubles with Black Jaguars

Quote:
Originally Posted by mjcoss View Post
Checked last night and no such luck. All look Jaguar connectors look fine to me. We also tested that the end to end termination was reading the correct resistance. So back to the same issue we had last year with CAN: Intermittent timeout of messages, with no clear cut root cause or solution.
The problem is one of two places, the wiring or the code.

You can quickly rule out the wiring by connecting your first jag to a computer and communicating with the bus using BDC-COMM (this pulls your software out of the loop). If that works then it is your code.

I would suggest getting ONE jaguar working over CAN. Verify that works, then extend your known working code to include communicating with more Jaguars.
One problem we ran into early on was sending too many messages onto the CAN bus at once. We were driving three groups of jaguars (master/slave configuration) using synch groups. We were not limiting the frequency at which the messages were being communicated, and things didn't run reliably. I don't know what language you're using, but you'll want to add a time delay or wait between transmissions to ensure you don't flood the bus.
This is an issue we saw over the RS232/CAN bridge. I'd expect this problem would be less pronounced using the 2CAN.
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