DP83869HM: Auto negotiation

Hi Toru-san, 

Clause 37 pertains to auto-negotiation on the MDI side between the PHY and the link partner's PHY. 

Babasaki Toru said:

GEN_CFG2 Register (Offset = 14h) [set = 2947h].

It means that GEN_CFG2[7] SGMII_AUTONEG_EN set "0".

This autonegotiation is between the MAC and the PHY when SGMII is used to communicate between the MAC and the PHY. Therefore, there is no need to disable this to meet clause 37. 

To turn off auto-negotiation, you can strap the pins depending on the functional mode of the PHY. 
Please refer to section 7.5.1. of the datasheet for more detail. 


Or, you can write 0 to bit 12 of register 0h for copper and 0 to bit 12 of register C0h for fiber/bridge mode. 




Please let me know if you have any other questions. 

Best,
J

Hi J-san,

Thank you very much for replying.
your advice is between DP8369HM and 1000BASE-X settings.  Is that correct?
I'd like more advice regarding between Ether MAC(SGMII) side and DP8369 settings

BR
Toru

Hi Toru-san,

If so, yes you can disable the bit you mentioned to disable SGMII autonegotiation.

Best,

J

Hi J-san,

Thank you.
Can I set to disable SGMII auto-negotiation and enable 10000BASE-X auto-negotiation?

Regards,
Toru

Hi Toru-san,

Yes, SGMII autonegotiation can be disabled and fiber autonegotiation can be enabled. In this case, SGMII will follow the fiber’s speed.

Best,

J

Hi J-san
sorry for late reply.
Thank you very much for answering.

BR
Toru