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TCAN4550-Q1: Issue configuring TCAN through SPI

Part Number: TCAN4550-Q1
Other Parts Discussed in Thread: EK-TM4C123GXL, , BOOSTXL-CANFD-LIN, TCAN4550

I am using TCAN4550-Q1 through the BOOSTXL-CANFD-LIN Evaluation board connected to an EK-TM4C123GXL launchpad, I based my code off the example with the msp430 here BOOSTXL-CANFD-LIN Evaluation board | TI.com. My issue is that when I'm running through the config for the TCAN4550-Q1, I am only getting 0x88888888 from the spi reads so I end up failing the config every time. My setup is: mosi - B7, miso-B6, CLK-B4, and CS-A4. I am using SSI_FRF_MOTO_MODE_0 with a bit rate of 2000000.

  • Hi Brendan,

    We've assigned this thread to one of our CAN experts, they should get back to you by the beginning of next week.

    -Bobby

  • Hi Brendan,

    Thanks for bringing your question to E2E!

    The TCAN4550 expects the nCS signal to remain asserted for the duration of a single SPI transaction. This includes the 4 byte header (R/W byte, 2 address bytes, length byte) and all subsequent data bytes. The nCS line should only deassert high once the entire SPI transaction is complete. See Figure 8-17 on the TCAN4550Q1 datasheet for an example of what this should look like. Please ensure the SPI configuration you are using is set to hold the nCS low per transaction rather than per byte.

    Let me know if you have any more questions. 

    Regards, 
    Eric Schott