USB Port on PoE HAT does not work

#1

Hello everyone,

some days ago I received a RockPi-E Rev1.2 together with a PoE HAT from Radxa.

PoE part works fine for both power and data, but I’m struggling to use the USB port, when I connect any USB peripheral (drive, mouse, keyboard, etc.) nothing happens, no changes with lsusb command before and after

I had a look to the PCB and I found out something weird to me, two components on the USB data lines are missing. Schematic of the PoE HAT are not released, so I can’t verify if this is normal or not.

IMG_20201031_094804
IMG_20201031_094804.jpg3120×4160 3.45 MB

Is it possible to have the schematic released, if not full one at least the USB part?

#2

You can track the PCB traces or test with an multimeter.

Is the USB port enabled in the DTS?

#3

I think this batch of 13W PoE HAT is for the Raspberry Pi 4, which doesn’t have USB function but power only. Is your poe pin header at the right position?

#4

I ordered one for RockPi-E, PoE connector is in the right position and PoE works fine

#5

I can do that, but without schematic it’s just gambling

#6

Could you please tell me the value of those resistors, I would like to solder them and test again.

I think your BOM for RockPi-E variant has an issue, because I got some pictures from WLANPi team and resistors are missing too

#7

@jack there is a clear problem with the PoE HAT I received, could you please give some support to have USB working?

What I need is the value of those two resistors, so I can add them

#8

I’m seeing the same issue with the 2 PoE HAT’s I have. USB port is not functional. I confirmed in the DTB the dr_mode is already set to “host”.

#9

I’ve confirmed that with current batch of PoE HAT(v1.1), the USB signal routing is wrong, that’s why it’s for Raspberry Pi 4 only.

#10

The resistor is usually 0 Ω for different options.

#11

with some help from my multimeter I understood the issue.

the two missing 0Ohm resistors are connected to the wrong pins on GPIO header (23-25 instead of 16-18)

This means USB will not work even if I populate the missing resistors.

Are you planning to release a new version to fix this problem?

#12

Yes, a new batch(v1.2) is under progress now.

1 Like
#13

So what are the options for those of us who purchased the current version?