2025-05-17 9:56 PM
I want to make a communication between 2 microcontrollers by can protocol i put after each microcontroller a can transceiver and the problem is that we send data but i other board we don't receive it, i mean after the second receiver we don't have proper output in RX,TX even it's CANH,CANL input of transceiver is ok and the transceiver doesn't have problem because i changed them but the problem remain! and i archived the codes if you want to take look...
if you know where the problem is pls tell me.
Solved! Go to Solution.
2025-05-20 1:20 AM
@ssharrafi wrote:
yes
Hello @ssharrafi ,
Sorry but ST resources are only dedicated to supporting genuine ST products. We are not committed to ensuring that clones/fakes products work properly with the firmware we provide.
This thread will now be locked. However, if you face difficulties while using genuine ST products, we’re here to assist you. Please feel free to start a new thread, and our team, along with community members, will be ready to help you with any issues/questions you encounter.
2025-05-18 5:47 AM
So if I understand You right, You have measured the CAN frame on the BUS and it's OK, but after the Transceiver the RX signal is always High.
If this is the case, You probably have a connection problem with Your transceiver. Can You tell us what Transceiver You are using?
Some Transceiver need the pin STD (or similer) to be pulled to GND to work.
2025-05-19 2:27 AM
Hello,
What board are you using? Blue pill?
2025-05-19 8:23 AM
Diagram what you've actually built/constructed.
Part# and wiring
2025-05-19 11:07 PM
I’ve documented the solutions I found here in order, so that if anyone else encounters a similar issue, it might help others. There were two main causes: one related to hardware and the other to software.
Hardware:
Ensure the wiring is correctly connected, and verify that the microcontroller provides the transceiver input. You can do this by measuring the signals with a multimeter.
Software:
The issue was that the filter name in the code did not match the "callback" function I was using. Correcting the filter name resolved the problem.
2025-05-19 11:09 PM
yes
2025-05-19 11:10 PM
yes it was the problem that the microcontroller didn't provide exact 5volts to my transceiver.
thanks for your comment
2025-05-20 1:20 AM
@ssharrafi wrote:
yes
Hello @ssharrafi ,
Sorry but ST resources are only dedicated to supporting genuine ST products. We are not committed to ensuring that clones/fakes products work properly with the firmware we provide.
This thread will now be locked. However, if you face difficulties while using genuine ST products, we’re here to assist you. Please feel free to start a new thread, and our team, along with community members, will be ready to help you with any issues/questions you encounter.