CAN communication not establish in S32K144 EVB

[RajG]

Hello all,

I have MPC5748G and S32K144 development boards. I have established CAN communication with the help of Processor Expert Can_pal component between MPC5748G and Arduino UNO board + MCP2515 and it works fine.

When I am trying the same Arduino UNO+MCP2515 with S32K144 board I am not able to establish any communication using same Can_pal component from Processor Expert. All the procedure to transmit and receive via CAN is also correct but I am having difficulty to connect S32 board with Arduino.  I have also given 12V supply for SBC on S32K144 board.

Can someone guide me through how to use and debug this type of issue, I do not have any other access to analyzers, hence using Arduino.

Thanks and Regards,

RajG.

[PetrS]

Hi,

be sure CAN bus termination resistors are placed on both boards.
Having S32K144 board unconnected from CAN bus, try to send message, and check ECR/ESR1 registers for errors. If see just ACK error and TX error counter ends in 0x80, this could mean SBC transceiver is active, but you got no ACK from other node, for sure.
If for example ESR1 shows zero, it says the module is not synchronized to the bus at all, no communication can be done, most probably RX line is held low by SBC. It seems SBC is no longer in default state (Forced normal) in which transceiver is enabled. From the factory the SBC comes in this Forced Normal mode and no special init is needed for the SBC and its CAN transceiver. If the SBC leaves this init mode (by clearing FNMC bit of the SBC configuration control register) then the SBC init must be done. Or restoring factory preset values can be performed as mentioned in SBC datasheet.

Also discussed here https://community.nxp.com/message/1047022#comment-1105605

BR, Petr

[RajG]

@PetrS the values of ECR/ESR1 is not getting updated at all, I also tried the sequence for SBC still no results. 

[PetrS]

Hi,

if SYNC, IDLE bits of ESR1 are not set, this mean module is not synchronized to the bus; RX pin seen low. You can try to measure level of the PTE4 pin. If this is low most probably transceiver and/or its supply is not enabled. try to measure V2 pin of the SBC. Restoring factory values as written in chapter 7.11.2 Restoring factory preset values of the SBC datasheet should help.
Or configure SBC through SPI.

BR, Petr