DP83869HM: 1000Mbit/100Mbit Copper to Fiber Media Converter Board

Hi Marco,

Thanks for posting the question on E2E. Someone from our team will get back to you by Tuesday next week.

-Regards

Aniruddha

Any news?

Aniruddha,

this is an urgent issue. Can you handle this with priority please?

Regards Bernd

Hi TI team,

is there a chance to get a response to this topic?

br

Armin

Hi Armin,

Sincere apologies for the delay. I hope we are able to continue to work together to close this issue.

Based on the datasheet language, the order of operations for this register operation may be significant. Please refer to Section 9.4.8.4 in the datasheet, register 0x1DF should be configured before registers 0x0, 0x10, and 0xC00. 

Additionally, what is the value of register 0x3?

Thank you,

Nikhil

Hi Nikhil,

I checked your recommended order of register configuration on our board, but I got the same link-problems as before.

The value of register 0x0003 = 0xA0F1

Best regards,

Marco

Hi Marco,

If I am understanding correctly, 100M Media Convertor Mode works correctly, but 1000M Media Convertor mode is not working.

For 100M Media Convertor Mode, does working correctly mean device links up and all data transfer works as expected?

For 1000M Media Convertor mode I have the following questions:

• Can you clarify what is meant by "can't communicate with the network?" Is there link, no data transfer, packets are lost, there are packet errors, etc.?
• Is RX_CLK active?
• Can you read back registers to confirm your writes have gone through?
• Can you provide screenshots of the RX_CLK for both 100M Media Convertor mode and 1000M Media Convertor Mode?

Thank you,

Nikhil

Hi Nikhil,

"can`t communicate with the Network" means that I see an Link on the copper and on the SFP side but I haven`t any data Transfer.

I measured RX_CLK but it`s not active. Why should we have an Clock at this pin? we use copper to fiber and not rgmii to fiber?

I read back the Registers and all of them get set.

Do you have any other idea? Maybe there is a mistake in the shematic?

Best regards,

Marco

wrong entry

Hi Bernd,

Thanks for providing the schematic. I will review the schematic and provide additional feedback by Tuesday of next week.

Thank you,

Nikhil

wrong entry

Hello,

Are you able to provide the full schematic including SFP connector, magnetics, straps etc.? For the portion of the schematic attached to this thread I have the following feedback:

• Remove pull-up on MDC, not needed
• Recommended 2-level strap resistor value is 2.49k. 2.43k should be ok, can confirm by reading registers 0x6e and 0x6f that straps are set correctly on power-up.

Additionally, rather than check RX_CLK, can you check CLK_OUT performance in both cases?

Thank you,

Nikhil