I want to use DP83867E with UbiSwitch to use all 11 ports, will it work

Hello. I am designing a carrierBoard for the ubiswitch.

I want to use Ports 0,9,10 in SGMII mode and I have selected DP83867ERGZR to be used as SGMII to cooper PHY.

Could You tell me if I could use that PHY? or should I select something different?

DP83867E is a pretty standard 10/100/1000BASE-T PHY with SGMII interface from Texas Instruments.

The 88E6393X has three PHY-less ports that support, Port 0, Port 9 and Port 10.

Port 0 supports:

Mode 1: SGMII/1000GBASE-X/2.5GBASE-X

Mode 2: 5GBASE-X

Mode 3: SFI/USXGMII

Ports 9 and 10 support:

Mode 1: SGMII/1000GBASE-X/2.5GBASE-X
Mode 2: 5GBASE-X
Mode 3: SFI/USXGMII
Mode 4: RGMII
Mode 5: RMII
Mode 6: MII

UbiSwitch puts only the SerDes pins on the stacking headers (see below), meaning you can’t use RGMII, RMII or MII on UbiSwitch. Since DP83867E supports SGMII though, that is not a problem for you.

So, you would need to connect your SGMII ports there.

I was going to go further in detail on this, but actually I think it’s easier if we just make and share an example schematic using the DP83867E for you. This will make your life a lot easier and avoid mistakes.

Give us a few days and we’ll share that for you.

Here is an example schematic showing the SGMII connection between DP83867E and UbiSwitch.

We also offer a free design review service. Once your design is complete, feel free to get in touch with us at info@botblox.org. We can sign your NDA if needed.

Hello. I appllied that schematic and have the following behaviour.

DP83867E link established LED is on (after connecting the cable).
DP83867E link activity LED blinks once a few seconds (it doesn’t blink in sync with any other LED on the switch)
I connect a device to the switch and the device sees the ethernet connection but can’t ping any other device connected to the switch.

I am using port 9 but I have three DP83867E connected to port 0, 9, 10 through SGMII and I would like to use all three with 10/100mb/s devices.

I cut the solder jumper SM1 according to Getting UbiSwitch ports working with a 1G SFP

How should I proceed from now? (both to get working port 9/10 and port 0)

Could you email us the schematic for your design, particularly showing the MAC to PHY connections for ports 0, 9, and 10, so we can review it?

ok. I will send you the design shortly.
I’ll only add that I didn’t notice any traffic on SGMII (with an oscilloscope). So if the switch has to initiate the communication, it doesn’t happen.

Got it. We’ll review that now.

It’s either…

  1. A PHY_ID issue on the DP83867
  2. A routing or PCB trace issue (please confirm you’ve done length match and matched impedance)
  3. A mismatch between the PHY setting on UbiSwitch and the DP83867. That would require a firmware update on the UbiSwitch. Thankfully we are actually in the process of doing that.

We will review and get back to you soon.