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Re: NetBSD 7.0 i386 panic during boot (Joerg Sonnenberger) writes:

>On Mon, Oct 12, 2015 at 11:21:41AM +0700, Robert Elz wrote:
>> ps: it would be interesting to know if there was any rational way to
>> develop a NetBSD to NetBSD USB protocol that could maybe be used to
>> replace serial consoles

>You don't need "just" a cable, but one with quite a bit logic in
>between. USB is not designed for host-to-host communication, so you need
>some form of mailbox in between. This is quite different from Firewire
>and derived interfaces.

There are such "cables", mainly used for data exchange. Nothing really

Then you have USB OTG which is a hardware extension that allows to switch
a port between host and device mode. Often used in ARM systems, I've never
seen it for x86. We don't support OTG.

Then you have USB Gadgets. This is a protocol that makes host and device
swap roles on a logical level without changing hardware. We don't support
the necessary device mode for one side, or the Gadgets protocol.

On the other side, USB as a low-level console is pretty limited. It
requires a complex software stack to work.

                                Michael van Elst
                                "A potential Snark may lurk in every tree."

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