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DP83825I: SMI read problem, every tenth read got answer

Part Number: DP83825I

Dear support,

I am using two DP83825i phy with common SMI interface connected to an FPGA.

PHY1: address set to 0
PHY2: address set to 2
MDC clock frequency: ~100KHz

I am testing the SMI interface by reading the PHYIDR2 register.
From address 2, i got no answer. (the phy not even try to pull down the line)
From address 0, i got answer only every tenth attempt. I see no difference with oscilloscope in the signal integrity when i got answer or not.
There is one of the simulation timing, measured on hardware as well:


If you have any suggestion to debug the problem I would be grateful.