> From: Erik Berls <cyber@ecst.csuchico.edu>
> Subject: Serial Consoles on HP9000/400
> To: port-hp300@sun-lamp.cs.berkeley.edu
> Date: Mon, 11 Apr 1994 19:02:28 -0700 (PDT)
> 
> Does serial consoles work on the HP9000/4xx?
> Any other status information regarding this class of machine would
> be helpfull,
> thanks,
> -=Erik.
> 
It should.  You need to interact with the boot ROM to tell it that the
serial port should be the console.  You need to put the RS232 card in "remote"
mode.  I don't remember the exact commands, but when the machine starts to
boot and gets to the "HIL Keyboard" message, type "C" and you will go into
"configuration" mode.  From there you do something like select IO devices and
then the RS232 and then set remote and save the configuration.  Sorry I don't
remember the exact details.

If you have an earlier 300 (370 or before), you do this by changing a dip
switch on the IO card.

From looking at the NetBSD sources it appears that you can also do this in
the kernel by setting "dcaconsole" to the appropriate unit number (e.g. 0).
I recommend that you don't do this however, since both ROM and standalone
boot messages will continue to come out to the display.  By changing the
EEPROM/dip-switch everybody will use the serial line.  This is useful for
debugging since you can run the serial line to another machine and then
rlogin to that machine from anywhere and "tip" to the console, interacting
with the boot ROM and standalone boot as necessary.

Another easy way is to just pull your display card out!

------------------------------------------------------------------------------