Thread: CAN reliability
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Unread 07-12-2010, 04:44 PM
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Re: CAN reliability

Quote:
Originally Posted by Radical Pi View Post
Just a quick confirmation for your assumption about the serial-to-can bridge. Assuming FIRST didn't change too much from the default Jaguar firmware, I'm looking at the default source code right now and it looks like it directly resends the body of the serial message over the CAN bus if the message is intended for another jaguar or if it's meant for all the jaguars. It looks like the CAN headers are added on in the process, so the serial message is only containing the device ID and the message itself. If the message is intended for the bridging jaguar, it never reaches the CAN bus and is just directly processed.
Really? That's not what I expected, but I'm glad you looked it up.
I suppose this means there could be a small difference in communication speed between the bridging jaguar and the rest.

Bot190:
I understand your reasoning now, thank you.
From this new information, it appears that a 6-byte data field can be sent, but a 10 byte data field can be received. The maximum data field length in CAN is normally 8 bytes, so perhaps those last two bytes are used for something else.
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Last edited by kamocat : 07-12-2010 at 08:43 PM.
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