Re: need a bit of early boot help

On 2025-11-11 06:00, Mouse wrote:
>> NetBSD 1.6.1 [...] stops in a suspicious place: Right after printing
>> "root file system type: ffs", on the next line, it prints an 'S' and
>> hangs.  [simh indicates this] is the first character of this date
>> stamp:
> 
>> Sun Nov  9 22:05:50 GMT 2003
> 
> [a second mail]
> 
>> After sending that last email I went back to the console.  It had
>> been sitting there for maybe ten minutes.  Suddenly it sprang to
>> life; the date stamp never finished printing (at least not that I
>> could see, but the console is only running at 1200 baud) but it
>> printed the 'B' that starts the "Building databases..." line.  It
>> printed a few more lines after that and has now been hung again for
>> several minutes.  I'm waiting to see if it starts up again.
> 
> It printed a few more lines in full, or the first character of each?
> If the former, were they printed at full normal 1200 baud, or did each
> character take a long time to print?  See below for the relevance.
> 
> I can hardly claim any particular insight into the 11/780 in
> particular.  But it does occur to me that everything
> before-and-including "root file system type: ffs" is printed from
> within the kernel, but that timestamp is printed by userland.
> 
> That may not be the relevant thing, though.  I don't know 1.6.1 in
> enough detail, but perhaps kernel output is polled but userland is
> interrupt-driven?  Maybe something is wrong with TXCS-driven
> interrupts?

That would be the case, yes. Unless I remember wrong.
Since output from the kernel works, we can at least say that there is 
nothing wrong with the serial port as such. And the booting process went 
fine.

And VMS also hangs after printing a banner... Which would suggest that 
there is something funny either with the printing on the console, but 
which is interrupt related, or something else is getting the machine 
stuck at an elevated privilege mode, preventing interrupts from being 
processed.

I would actually probably suspect something else isn't completing, and 
the processor is stuck at some elevated prio. The console is probably 
working just fine, including when interrupt driven. But something else 
is not.

I assume we're talking about a real machine here. So it has actual 
Unibus. Simple suggestions would be to remove everything not absolutely 
required to get the machine running, and really make sure you have bus 
grants in all Unibus slots not having a card in it. Also, make sure the 
NPR jumper is in place. This one can be a bit tricky, since it's 
actually a wire on the back side of the backplane, which might have been 
cut. There a double height bus grant cards that also covers the NPR 
signal, but the small square ones do not.

And if the Unibus isn't properly configured, you can probably get things 
hung/stuck for some time.

   Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: [email protected]             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol