On Tue, 21 Jul 1998, Ruschmeyer, John wrote:

> > 1) Is there any reason that the dead NVRAM might keep me from booting
> > from tape?
> 
> [ Yes, a dead NVRAM will prevent the machine from booting.  Installed
>   new NVRAM. ]
>
> The system resets and seems to now believe the NVRAM is valid. It proceeds
> through the diagnostics, initializes memory, and gives me the prompt to
> press any key to enter extended diagnostics or press "e" for echo mode. If I
> enter "e", I get a message that output will be echoed to the screen. Either
> way, however, the system appears to hang at this point.


It looks like your machine may be stuck in diagnostic mode.  On all Sun3
machines except the 3/80, diagnostic mode is enabled and disabled with a
switch on the exterior of the machine.  The 3/80, however, reads the
diagnostic mode setting from NVRAM location 70b.  Use the ''q'' command at
the monitor prompt to fix it.

  > q 70b
  70B 12? 06
  70C 00?
  >

But, because you can't seem to make it to the monitor prompt you may have
a problem.  If you are using a serial console, make sure that you remove
the frame buffer.  The NVRAM directs the monitor whether it should use the
serial port or the frame buffer and keyboard as the system console.  Just
because you see activity on the serial port during diagnostic mode does
not imply that the ROM monitor is going to use it as the console once the
diagnostics finish.  By removing the frame buffer you will force it to,
regardless of the NVRAM settings. 

-J