Re: USB-serial adapter suggestions needed

From: bob prohaska <fbsd_at_www.zefox.net>
Date: Sun, 14 Jan 2024 16:36:04 UTC
On Sun, Jan 14, 2024 at 10:52:34AM +0000, void wrote:
> Hi Bob,
> 
> The following *may* be useful to you..
> 
> (rpi4 context)
> 
> I've noticed, both on 13-stable and 14-stable, that, if both
> onboard usb2 ports are utilised (eg keyboard & mouse) that
> signals keyboard<>mouse interfere with each other.
> It's easy to reproduce this problem. It's been a while
> since testing that exact context, though.
> 
> When running headless, I needed to make sure the ups cable
> (serial) was plugged into the remaining usb3 port (and not usb2
> where a wifi dongle was plugged in) because communication from
> the ups would make the wifi page down if both were plugged into the usb2
> side. The wifi would make the usb serial misbehave (caused 'no signal coming
> from ups' type of error) too.
> 
> I've had to press the hardware into service so cannot produce detailed error
> output for now.

At the moment I have two Pi4's, one running FreeBSD-current. That machine
has a USB hard disk (boot device) in one USB 3 port, an ft232 usb-serial
adapter (probably USB 2) in the other USB 3 port, with a keyboard and 
mouse pulugged into the two USB 2 ports. I've not noticed any problems
with either keyboard or mouse.  Of course, all are plugged in all the
time, so there's only one enumeration happening, at boot.

The Pi4 that I reported the problem with runs 64 bit RasPiOS.
It has a single USB 3 hard disk (boot device) and a usb 2 keyboard 
with an internal hub, the mouse being plugged into the hub. It 
boots fine with that combo, I haven't tried moving the mouse to
the other usb 2 port. When it's convenient to provoke a crash
I'll try. 

I intended the mention of RasPiOS trouble with USB as recognition
that USB is imperfect. I didn't mean to suggest that if Linux
can't do something FreeBSD shouldn't try. 

Thanks for writing,

bob prohaska