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JDeff's avatar
JDeff
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5 years ago

TSE MAC phy MDIO write not working.

I am able to read register 0 of my phy by initiating a read command to address xA0 in the Avalon bus. the result is x1140. However if I try to write to this same address, no MDIO transaction takes pl...
JDeff's avatar
JDeff
Icon for New Contributor rankNew Contributor
5 years ago

Hi Dlim,

My core instantiation includes the PCS. My understanding is address space 0 is unavailable when using the PCS function.

  • My Avalon clk is 100 mhz, and the divider is set to 80, so i should have an MDC of 1.25MHz
  • I write x"0F" to addresss x"10" before initiating a read or write to address x"A0". My phy address is "1111"
  • Again, I am able to read data from the phy, but a write locks up the avalon interface with waitrequest held high and no transaction initiated on the MDIO bus
  • I have MDIO connected as below :

MDIO <= mdio_out when mdio_oen = '0' else 'Z';