As to the 3 Qs (only apply to my experience):

> 1. When the serial port goes ballistic, does the console still behave
> normally

N/A (serial console)

> 2. Does disconnecting the serial connection and reconnecting it either
> reset the connection back to a login prompt or at least start things
> running again?

Already tried.  Nope.

> 3. Have you checked to see if NetBSD is receiving handshaking signals
> such as control-S's and control-Q's, and if so, checked to make sure
> it's not just missing a control-Q or a CTS or whatever (test by hitting
> control-q)?  I doubt it's something that simple, but if it were, it
> would simply be minor loss, and not something drastic like a complete
> crash.

It's not a crash.  It's more like the driver stalled in a weird state
or something.  Nothing (c-Q or cycling modem signals) brings it back
as far as I tried.

> BTW, forgive me for my ignorance, as I've never used dt.  Will dt
> run over a serial console or is it too graphically oriented?

Suffice it to say dt opens /dev/grf0 and /dev/adb.

ken