CANbus - 18F4585 - Fried CANTX pin?

Thread Starter

atferrari

Joined Jan 6, 2004
4,069
Nodes with 18F4585 + 65HVD251 transceiver.

Tested for hours a 3-node network.

All nodes run the same software (100% equal), transmitting only when a pushbutton is pressed. (This is my first test with real hardware).

Messages from one of them is never received by the other two nodes, BUT that node, receives ALL messages from the other two.

After swapping transceivers with exactly same result I decided to swap also the micros. Found a micro that, no matter in what node it goes, the above symptons repeat.

Scoping its CANTX pin shows activity but CANH and CANL show that a shorter message is sent every time. (I can say that because messages are programmed to be EQUAL in all nodes.).

Masks not used and filters exactly one for each message.

Just in case I erased and reprogrammed the (culprit?) micro to no avail.

Should I discard any further chances and consider it a fried micro for CAN use? (Brand new one, out of the box.) And expensive! :mad:
 

Thread Starter

atferrari

Joined Jan 6, 2004
4,069
A last moment change in the third node was not compatible with the two previous ones.

Software was not 100% equal!.
 
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