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DP83848Q-Q1: Transmit and receive links

Part Number: DP83848Q-Q1

Hi Team,

Could you help tell how to operate BIST to verify the integrity of the transmit and receive links of DP83848Q? (Based on 100 m/s data stream) Thanks.

Best Regards,


  • Hi Cherry,

    Here are the steps to run BIST on the DP83848:

    1. Enable loopback mode by setting the LOOPBACK bit of BMCR register to 1
    2. (Optional) Set the bit PSR_15 in PHYCR to use 15 bit pseudo random sequence, instead of the default 9 bit sequence
    3. Start the BIST by setting the BIST_START bit of PHYCR register to 1
    4. Read the results by reading the BIST_STATUS bit of PHYCR, to check whether it is a 1(pass) or 0(fail)

    Also for 100M operation, the BMCR value would then be 0x6100. 

    Are you seeing any issues with your PHY or are you just verifying that it is functional?

    Best regards,