magic switch to ARC console?

[der Mouse <mouse%Rodents-Montreal.ORG@localhost>]

I just turned on my PWS600au for the first time since...January 18th,
from what I can tell.  It appears to have decided to switch itself from
SRM, which I've been using for as long as I've had it, to ARC: I get a
pseudo-graphics display rendered with X3.64 cursor motion and the like,
it calls itself "AlphaBIOS Version 5.67", and it offers to boot Windows
NT and nothing else.  (Which of course it couldn't do even if I told it
to, because Windows isn't there to be booted.  I haven't tried telling
it to boot anyway, because I fear what could happen when NetBSD tries
to make SRM calls and gets ARC semantics instead.  At best I would
expect it to error out; at worst it could do something relatively
irreversible like wipe the drive.)

Presumably the machine has both, or it would not even have been
possible for it to switch on me like this.  So, my questions are, (1)
how could this have happened, and (2) how do I switch it back?

As for the former, I can only speculate.

As for the latter, it says things like "Press F2 to enter SETUP", but I
have no idea what octet sequence it's expecting to see on the serial
line for such things.  Actually pressing F2 gives me ESC-[-1-2-~, but
that doesn't seem to do it; all that really means, though, is that the
terminal emulator doesn't agree with the ARC on this matter.

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