Strange Problem on DECstation 2100

[Sean Caron]

Hi Robert,

Will it MOP boot NetBSD successfully? Something to help give you a feeling
if the issue is intrinsic to the machine or it's just something with Ultrix
4.5.

You can always try swapping network cable, switch port, AUI transceiver...
sometimes this stuff can have some unexpected effects... I had an old
SPARCstation 10 years ago that wouldn't boot from any media... or it was
just continuously locking up, crashing... I don't remember... but after
replacing every part in the box, finally swapping another SPARCstation 10
entirely and having the issue persist, I found it was, believe it or not, a
bad Ethernet cable!!

Best,

Sean


On Sun, Dec 21, 2014 at 4:13 AM, Robert Jarratt <robert.jarratt at ntlworld.com
> wrote:

> I have been trying to get my 2100 working. I have been using MOP to boot
> the
> machine and try to install Ultrix, although this is not working for some
> other reason at the moment. Until this morning, it was booting from MOP
> just
> fine, but now it, after leaving the machine overnight and not doing
> anything
> to it, I get this when I try to MOP boot:
>
>
>
> Ultrixload - V4.5  Thu Sep 14 07:07:53 EDT 1995
>
>
>
> Excptn:    (vtr=NRML)
> Excptn pc: 0x807001f8
> Creg:      0x30000010(CE=3,EXC=RADE)
> Sreg:      0x30000000(CU1,CU0,IPL=8)
> Vaddr:     0xaaaaaafe
> Sp:        0xa13fbba8
>   0xa13fbba8 : 0xaaaaaaaa 0x80701310 0xa0003b60 0x80700000
>   0xa13fbbb8 : 0xaaaaaaaa 0xaaaaaaaa 0xaaaaaaaa 0xaaaaaaaa
>   0xa13fbbc8 : 0xaaaaaaaa 0xaaaaaaaa 0xaaaaaaaa 0xaaaaaaaa
>   0xa13fbbd8 : 0xaaaaaaaa 0x80700048 0xa00039c8 0xaaaaaaaa
>   0xa13fbbe8 : 0xaaaaaaaa 0xaaaaaaaa 0xaaaaaaaa 0x00000000
>   0xa13fbbf8 : 0xaaaaaaaa 0xaaaaaaaa 0x00000001 0xa00039c8
> exit(-1)
>
>
>
> The really strange thing is that if I attach a CD-ROM drive and boot off
> that first, then try the MOP boot after that, the MOP boot works! Before
> anyone asks, I have other problems which mean it won't successfully install
> Ultrix from the CD-ROM, and I am trying the MOP route because of this. The
> CD-ROM problem is something to do with the block size, I know about the
> block size jumper and have tried with the jumper installed and removed.
>
>
>
> I have a workaround which is to connect the CD-ROM, boot off the CD-ROM,
> let
> the CD-ROM installation fail, then unplug power from the CD-ROM and boot
> from MOP. But that is horrible, and wasn't necessary until this morning.
>
>
>
> Any ideas?
>
>
>
> Regards
>
>
>
> Rob
>
>