Luca Ferrario

Devkit S12ZVC : CANH stucked High

Discussion created by Luca Ferrario on Jan 14, 2020
Latest reply on Jan 16, 2020 by Diana Batrlova


I've got a problem with the CAN bus, I've configured the MSCAN0 with code warrior expert (bit rate: 250 kbit). The system works fine in loop back mode: I can send data and the event CAN1_OnFullRxBuffer() is called, tha masks also work fine. I've got a problem when I want to use the CANPHY with CANH and CANL pins of the board: the CANH pin is stucked at high voltage!

I configured the CANPHY in this way:


CP0CR_CPE = 1; //Module Enable
CP0CR_SPE = 1; //Split Enable


and the M0C0RR[2:0] to 000


Did i miss something in the configuration of the CANPHY?


I've also tried to probe the data between CANPHY and MSCAN0 with the M0C0RR[2:0] configuration 0b100, in order to use the pins TXCAN0 and CPRXD0 as probes.


Channel 0: MSCAN0 TXCAN

Channel 1: MSCAN0 RXCAN


Channel 2: CANPHY0 CANH

Channel 3: CANPHY0 CANL

The RX data is coming from a PCAN simulator, if  the simulator is stopped no data is present on channel1 and channel 3.


Thanks for your help!