🚀 go-pugleaf

In article <1992Aug4.211639.25436@news.iastate.edu>, njohnson@sysad.cnde.iastate.edu (Neil Johnson) writes:
> 
> 
> I'm having problems installing a RZ25 in a DECstation 5000/125.

Disclaimer, I've never worked with DECstations...
> 
> If I just connect the drive by itself to the DECstation, It can't find
> it.

Have you checked the terminators? All SCSI busses must have two, and only
two, terminators. Normally there is one at the CPU end. If you're fitting
an extra disk alone that disk should have a terminator. I would guess that
there is some sort of external terminator plug for the SCSI socket
on the CPU box, so normal practice would be to leave the disk unterminated
and plug in the external terminator. When you add other devices the terminator
should be moved to the end of that chain.

The terminators on the disk drive will probably be inline resistor packs,
things which look like very slim ICs but with only one row of 8 pins. Try
pulling them out of their sockets before installing the disk.

Wrong termination on a SCSI bus can cause all sorts of bizarre problems
> 
> If I connect an external disk or tape, it then reports that it has six RZ25's
> connected and nothing else.

That sounds like one of your external devices has the same SCSI ID as the
RZ25
> 
> If I just connect the external drives and not the RZ25 the 125 finds them fine.
Definitely sounds like an addressing or termination problem.
> 
> I have checked the SCSI ID jumpers and they at least match what the DEC
> documentation says the should be set to.

Are all the IDs definitely unique? Never mind if the suggested IDs in the
docs aren't, all _must_ be unique, even if they don't match what the docs
say. The CPU will probably be 7, conventionally the boot disk should be
fairly low (like 0), then tapes, then a CDROM if you have one.

> 
> HELP! (I've been upgrading workstations for 3 weeks now and I WANT TO GET IT
>  OVER WITH SO I CAN GET ON WITH MY LIFE! ARRRRGGGGGH!)
> 
Thats not too bad. Its when you spend 3 weeks upgrading ONE workstation
that you can get really pissed...

Steve