Raspberry Pi Zero W "USB device not recognized" after connecting ZERO4U

[ilan_sw]

Hello,
I'm working with Raspberry Pi Zero W. I SSH to it via micro USB without problem, as described in this manual:

https://www.thepolyglotdeveloper.com/20 ... cable-ssh/

Now, I connected a ZERO4U to it for more USB connections.
When I am connected to it via WIFI, it works, and the USB ports also work.
However, when I connect it to my PC (either via the original micro-USB on the Pi Zero or the mini-USB on the ZERO4U) it show the message:
"USB device not recognized".

The problem goes away when I remove the ZERO4U.

Is this fixable? I must be able to SSH to it via USB, so wireless workarounds are unfortunately not relevant.

[Ernst]

However, when I connect it to my PC (either via the original micro-USB on the Pi Zero or the mini-USB on the ZERO4U) it show the message:
"USB device not recognized".

The problem goes away when I remove the ZERO4U.

Is this fixable? I must be able to SSH to it via USB, so wireless workarounds are unfortunately not relevant.

Is this fixable? No, works as designed.

Without ZERO4U the Pi0 connected to a PC with a NORMAL USB cable is working as a device (= Gadget).
With ZERO4U the Pi0 is a host because the connection to the ZERO4U is like using an OTG cable.
You can not have both modes at same time.

[Andyroo]

There is a note at the bottom of the ad that states:

Remarks: if you ever enabled Ethernet Gadget on your Raspberry Pi Zero, you will need to disable it to use Zero4U. You can either comment out the “dtoverlay=dwc2” in /boot/config.txt, or plug an OTG adapter to the data micro USB port on Raspberry Pi Zero.

(From here)

Unfortunately, the OTG adapter will disable the ‘Ethernet Gadget’ mode as well according to the manual pages 9 and 10

It reads like it’s one or the other I am afraid.

[fruitoftheloom]

Hello,
I'm working with Raspberry Pi Zero W. I SSH to it via micro USB without problem, as described in this manual:

https://www.thepolyglotdeveloper.com/20 ... cable-ssh/

Now, I connected a ZERO4U to it for more USB connections.
When I am connected to it via WIFI, it works, and the USB ports also work.
However, when I connect it to my PC (either via the original micro-USB on the Pi Zero or the mini-USB on the ZERO4U) it show the message:
"USB device not recognized".

The problem goes away when I remove the ZERO4U.

Is this fixable? I must be able to SSH to it via USB, so wireless workarounds are unfortunately not relevant.

The only way is to use a USBNET Cable as that negotiates host to host connection:

viewtopic.php?f=36&t=131042

[thagrol]

That's expected behaviour.

There is only one USB port on the SoC. It can do either slave/device mode (e.g. ethernet gadget) or host mode (ZERO4U) at a time.

If dwc2 is loaded and in dual role mode it can hot swap but be aware that using a USB hub in this configuration will kill performance on the zero. At least in my experience.

If you must use a ZERO4U get a couple of cheap USB to ethernet dongles and use those to connect to the PC.

Edit:
If you've connecting the ZERO4U via the pogo pins, it could be behaving oddly.

ZERO4U appears to have no way to pull the ID pin of the USB port low to indicate to the zero it should act as a host so with dwc2 enabled and no otg cable connected to the zero it will always come up as a slave and the ZERO4U will not be recognised.

Reverting to the dwc driver forces the zero into host mode.

Now the next problem.

Connecting the ZERO4U via the pogo pins/test points and plugging something into the zero's micro USB port is the same as using a Y cable to connect two devices to a single USB port. It simply won't work. Without a hub, you can only have one device one each end of a USB cable.