2020-05-19 09:03 AM
I'm using the STM32F765VIT in a custom board and Trying to test CAN1 CAN2 and CAN3. Is it possible for me to send CAN data from CAN1 to CAN2/CAN3 and vice versa? I have CAN transceivers in them if you had that doubt. I'm trying to send data from CAN1 to CAN3 but In the CAN1 Transmission Status register I get the ACK error. Will CAN be able to communicate only with external devices and not within itself? I have tested the CAN loopback for each of these but I'm interested in testing from CAN1 to CAN3
2020-05-19 11:20 AM
Check that you have at least half a meter of twisted-pair cable between nodes and that the cable has termination resistors at each end. Assuming the transceiver on each node is operating and both nodes run from same clock and have same bit times it should work, unless the clock rate is too fast. CAN likes to have some separation between nodes; TI recommends 50cm for their transceivers. Termination should be a 120 ohm resistor across the twisted pair at each end.
Jack Peacock