Thread: CAN reliability
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Unread 12-07-2010, 15:41
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Re: CAN reliability

Quote:
Originally Posted by Bot190 View Post
Looking at the Can Jaguar library for C++, The maximum size of a sent message is 10 bytes, as was previously determined, and the maximum size of a received message is 14 bytes.
This assumes that a separate message is sent for every request to every jaguar. In this experiment 5 jaguars were used, this would limit the requests for information to 4, but limits the data being received to 3 messages.
Please correct me if I'm not thinking about this right, or if anything looks off.
It seems I don't quite understand their thinking. The maximum length of the data field in CAN is 8 bytes, so the maximum length should be 12 bytes. (I suppose it's true the Jaguars don't have any messages with data fields longer than 5 bytes)
Perhaps there is some error handling in the message returned, which would be added on by the main Black Jaguar?

You are correct that a separate message is sent to each jaguar, in most situations. There are some messages (heartbeat and enumerate) that are sent to all devices. I'm pretty sure that the main Black Jaguar acts both as the master and a slave on the CAN bus.
I don't understand where your numbers (4 and 3) came from. Could you please elaborate?
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