serial console on 8.x (probably sio vs uart)

Garance A Drosihn drosih at
Fri Sep 12 03:21:26 UTC 2008

I recently updated my 8.x test system from late-june to early-Sept,
and in the process I seem to have lost my serial console setup.
It's pretty likely this is related to the change from sio(4) to
uart(4), but I do believe I have done everything that I needed
to do to track that change.

After I boot up, the only /dev/tty* devices I have are ttyv0
through ttyvf.  I've installed the new /etc/ttys and a new
/boot/device.hints, though frankly device.hints has always
been a magic-box to me, so I just blindly copied what was in
GENERIC.hints and changed hint.uart.0.flags to be "0x30".
(that's what I used to do to get sio0 as the serial console)

I checked the documentation (well, a little), but it
seems that documentation is still geared towards sio0 (which
certainly makes sense).  For instance:

Based on reading a number of posts, my current guess is that
the problem is that I'm booting up an older (6.x) loader, and
then using that to load in the 8.x kernel.  I get the impression
that the newer loader includes changes to make uart work better
wrt the speed it expects to use on the serial port.  Is that a
reasonable guess?

(as to *why* I'm using and old boot loader, that's a long story
that I'd rather not get into right now.  I just want to know if
it's likely that would be why I have no serial ports now that I've
upgraded to the uart-based system...).

Garance Alistair Drosehn            =   gad at
Senior Systems Programmer           or  gad at
Rensselaer Polytechnic Institute    or  drosih at

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