DP83848K: Link status is valid (Link Status =1 in BMSR register), but cannot successfully pin link partner, why

John11513

Part Number: DP83848K

Tool/software:

Hi Experts,

Customer is using DP83848K in their equipment. They are doing some test with this setup: the equipment is connected to a PC directly through a short piecs of CAT5 Ethernet cable. They apply EFT on power supply cable, they found the communication terminated and PC cannot successfully ping their equipment after EFT until the ethernet cable is disconnected-and-connected again. While they checked the Link Status bit in BMSR register (bit2) and found Link Status=1. I cannot understand why Link status is valid but communication cannot be established. How should they handle this problem?

Thanks,

John

5 months ago

0 Gerome Cacho 5 months ago

TI__Mastermind 39795 points

Hi John,

Thanks for your query. One of our Apps Engineers will be responding to you shortly. Thank you for your patience.

Sincerely,

Gerome

0 David (ASIC) Liu 5 months ago in reply to Gerome Cacho

TI__Guru**** 176811 points

John

Can you please share their setup block diagram, schematic and full register dump from 0x00 to 0x1F?

They apply EFT on power supply cable, I assume this is a separate cable from the Ethernet cable. If this is the case, how far away is the power supply cable from Ethernet cable?

If you disable AN and force speed, do you see the link down issue?

Thanks

David

0 David (ASIC) Liu 4 months ago in reply to David (ASIC) Liu

TI__Guru**** 176811 points

John

I will go ahead and close this e2e thread. You can reply back to this E2E thread or create a new one if you need additional support.

Thanks

David

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DP83848K: Link status is valid (Link Status =1 in BMSR register), but cannot successfully pin link partner, why