Re: Raspberry Pi 4B does not detect devices in USB 3.0

On Tue, Feb 15, 2022 at 6:22 AM Daniel O'Connor <darius@dons.net.au> wrote:

>
>
> > On 14 Feb 2022, at 23:10, Archimedes Gaviola <
> archimedes.gaviola@gmail.com> wrote:
> > I just tried my new RPI4 board and it seems to work fine the same as my
> old board. I just observed that the problem is when my VFD (vacuum
> fluorescent display) device is connected to either of the two USB 3.0
> ports, this device having uplcom(4) driver is not detected.
>
> I wonder if the VFD is causing interference - it likely has a high voltage
> supply and those are notorious for generating electrical noise.
>
> > It's a Prolific USB-serial device having PL2303 chipset. However, when
> plugged-in to USB 2.0 ports, this device is detected and functioning. I can
> send characters with the echo command and redirect it to /dev/cuaU0 for
> display without any problem. Other observations when this VFD device is
> connected to either 3.0 ports, the 2.0 ports will not function i.e.
> plugging-in any USB devices like my keyboard or my EMV reader. When this
> device is also connected to either of the 2.0 ports, the other 2.0 port is
> functioning for other USB devices while 3.0 ports are not. I attached two
> dmesg outputs when the device is detected with 2.0 ports and undetected
> with 3.0. I also include kldstat and usbdump.
>
> I would be curious if putting the VFD on a longer cable, or wrapping the
> cable through a ferrite, or using an external hub fixes it.
>
> Any of those would give a bit more isolation between the VFD and USB3
> hardware.
>

Thanks Daniel for your recommendations, I've tried extending it to a long
cable and using an external USB hub however the outcomes were still the
same, it cannot be detected. As per checking, this device has a default
ferrite bead clamped over its USB cable.

Using the same RPI 4B hardware, this VFD device has been tested as well
with OpenBSD 6.9 and CentOS 8. They both work with USB 3.0 except OpenBSD
system will panic the first time you plug-in the device but will work fine
after a forced reboot or when you unplug and plug back the power.

Thanks,
Archimedes