DP83869HM: DP83869HM EVM

athur hsu

Prodigy 150 points

Part Number: DP83869HM
Other Parts Discussed in Thread: DP83869

HI TI guys

The DP83869 evm runs in 1000M media converter, but one of stranger thing is the copper interface always be running in 100Mbps.

The register is setting on the below

x01DF -> 0044

x01EC -> 1FFC

x0000 -> 1140

x0010 -> 5048

x0C00 -> 1140

Do you have any suggestion?

2 SFP module in plugged in the SFP cage and make sure the module is OK.

The FX_VCC is external power, normally the SFP module power consumption is 170mA @3v3, but in this case the SFP power consumption is only about 120mA @3v3, also it is no optical power output.

Can you please let me know the situation?

over 5 years ago

0 Hung Nguyen92 over 5 years ago

TI__Expert 5670 points

Hi Athur,

How do you determine the link speed on the copper interface? It also depends on the link partner. Please make sure the link partner supports 1000Base-T speed.

Please read the following registers when the copper link is up and SFP with fiber cable is connected to a link partner:

0x0004

0x0009

0x0011

0x0C01

Regards,

Hung Nguyen

0 athur hsu over 5 years ago in reply to Hung Nguyen92

Prodigy 150 points

Hi Nguyen

The two link partners are one desktop support 1Gbps RJ45 (fix on 1Gbps full duplex), another one is 1000M media converter.

Read the register as below

0004 -> 0181

0009 -> 0300

0011 -> 1300

0C01 -> 6149

The LED 0~2 set on pull-low, for auto-negotiation. I think the strap setting should be fine.

It might be something wrong on register seeting.

0 Hung Nguyen92 over 5 years ago in reply to athur hsu

TI__Expert 5670 points

Hi Athur,

From register readouts you provided, you don't have link on both copper and fiber.

Can you read register 0x6E?

Also providing schematic of DP83869 portion will help.

Regards,

Hung Nguyen

0 athur hsu over 5 years ago in reply to Hung Nguyen92

Prodigy 150 points

Hi Nguyen

1, 100M media converter works well.

2. 1000M media converter is still not working.

1000Base-X is linking up.

1000Base-T is still shunt down.

I have read 0x0011, the 1000Base-T connection is always unstable.

attach files are all register setting and schematic.3487.CV4-S1-4111L.pdf

0 Hung Nguyen92 over 5 years ago in reply to athur hsu

TI__Expert 5670 points

Hi Athur,

From your schematics, the center taps of the magnetics are connected to VDDIO 3.3V, which is not recommended. You also have 4.7pF cap on each MDI pin, which is not recommended either.

See section 10.2 of the datasheet for recommended copper connection, as well as magnetic requirements.

See also EVM design for your reference http://www.ti.com/lit/ug/snlu237/snlu237.pdf

Regards,

Hung Nguyen

0 athur hsu over 5 years ago in reply to Hung Nguyen92

Prodigy 150 points

Hi Nguyen

Thanks for you suggestion, it is working.

Interface

Interface forum

DP83869HM: DP83869HM EVM