DP83TC812S-Q1: 812 phy link issue

Hi Yang,

I have a few questions in order to better understand your issue:

• Are you able to read registers back from PHY?  This confirms PHY is not in sleep mode.
• Are you using indirect register access sequence?  This is detailed in "Extended Register Space Access" of data sheet.
• Have you tried strapping PHY into autonomous mode.  If so, is there any difference in behavior?
• What link partner are you using?  Is there any link partner dependency?

Thanks,

Drew

Hi Drew Miller1:

• Are you able to read registers back from PHY?  This confirms PHY is not in sleep mode.

        ------- yes , we can read and write register success

• Are you using indirect register access sequence?  This is detailed in "Extended Register Space Access" of data sheet.

        -------- yes , we reference this to access the mdio register

• Have you tried strapping PHY into autonomous mode.  If so, is there any difference in behavior?

        -------- yes ,we try to rework the board to remove resistor then the phy go to auto mode , the phy could link. and the eth data could transfer success

• What link partner are you using?  Is there any link partner dependency?

        --------I used vector to test link and eth data transfer

Thank you

Hi Yang,

• After writing 0x18B = 0x1C4B, can you read back 0x18B to confirm register is set correctly?
• Is DP83TC812 configured as master or slave?  If you switch master/slave, does this impact behavior?
• You could try PHY soft reset 0x1F = 0x4000 to see if this impacts behavior.

Thanks,

Drew

Hi Drew Miller1:

• After writing 0x18B = 0x1C4B, can you read back 0x18B to confirm register is set correctly?

         ------ yes , set success, and read back value is 0x1C4B

• Is DP83TC812 configured as master or slave?  If you switch master/slave, does this impact behavior?

       ----- we config is as 100base-t1 slave, switch master and slave is not imapct something 

• You could try PHY soft reset 0x1F = 0x4000 to see if this impacts behavior.

       ------ I set it , still could not link and set after I read back 0x1f is always 0.

Tank you

Hi Yang,

Apologies for the delay.

Which version of the open alliance configuration script are you using?

https://www.ti.com/lit/an/snla389f/snla389f.pdf

Thanks,

Drew

Hi Drew Miller

Do you have the linux driver for this phy.

we need enable it in linux side

Thank you