> It doesn't have a hole for CD-ROM drive in front plastic 
> panel and i'm apparently too dumb to figure out how on earth 
> a CD-ROM could fit there
> - unllike PC enclosure it doesn't seem to have that plastic 
> thingy that can be removed or replaced at will. So .. do i 
> need special plastic thingy to replace this one if i want to 
> add a CD-ROM ? WHile i'm at it, how do i detach the existing 
> plastic thingy ? I'm afraid to use force as i don't want to 
> damage the enclosure :)

Start by typing "VAXstation" or something similar into
http://vt100.net/manx/ and you should end up with
a bunch of likely looking manuals.  You need to find
almost any of the VAXstation 3100 owner's manuals.
There are two styles of box (one with two storage 
"tiers" inside, and one with only one). Other than
that, pretty much everything else is identical.

If nothing crops up, I do have a scan of the
VAXstation 3100 Model 38 Owner's Manual 
(EK-VSM30-OM-002) which I can either upload
to an ftp site, or possibly make available via
someone else to whom I've uploaded it.

The manual does show you where the panel is attached,
and it's fairly easy to remove if you gently press
in the right places (at the bottom?) pushing from
inside to out. But then you either need to leave it open
(which looks ugly) or find the right size panel for
whatever you are adding (3.5" floppy, TZ30 or CDROM).

> The only PCB that i can access inside the box is obviously 
> SCSI controlelr (it has NCR chip). It also has two geatures 
> i'm not sure what function they serve: first is a square 
> chip, about the size of a CPU with number starting with 21... 
> on it; i believe DEC labells their (CPU) chips this way; so 
> what is this chip ? 

No idea - but probably a custom DEC controller chip. IIRC
pretty much *all* DEC chips are 21-xxxxx, certainly not
just the CPU chips.

>                     Second thing is a two-row, 108 or so pin 
> male connector (pins are close together like those of 68-pin 
> SCSI connector); what is this connector used for ? 


> Below that PCB and HD is a steel plate which i'm apparently 
> unable to remove - i unscrewed the all three screws on the 
> right side (opposite of the PSU) and both screw-like thingies 
> in the front so they popped out from bottom plate. I don't 
> see any other screws there yet i cannot (re)move the upper 
> steel plate. Are there any screws on the back (perhaps near 
> that propertiary 68-pin connector) still holding it ?

My recollection is that there is at least one thumbscrew on
the back. There may also be another thumbscrew that connects
to a strap that goes onto the PSU. I forget whether it is the
upper or lower tray that has this (and I also forget whether
the BA42A is the taller one with two levels of storage or the
one with only one level ...)

If that doesn't help, let me know and I'll pull a BA42A
out of the pile and open it up to see.

> My HD is RZ26L-W, made by Quantum. I can't find any info 
> about this drive via Google (tried "rz26l w quantum"), just a 

Again Manx will point you at a few bits of info that DEC
published about this drive.

> says something about 8-bit transfers during bootup; according 
> to what little info i could find this drive is not SCSI-1 but 
> SCSI (-2 ?) Wide drive so i don't understand why it is so 
> slow and what that 8-bit blurb is all about ? 

I believe that it is SCSI-2 but it's narrow, not wide.

> Is there some way to speed up that drive (apart from throwing 
> it out the
> window) ? 

It's an old drive. The reason people keep them around is
that the VAXstation 3100s (all of tehm) have a restriction
to do with booting from drives bigger than about 1GB
(see the OpenVMS FAQ for the gory details). It's not
such a problem for NetBSD (IIRC) but the drives are
still useful.

> Is there any way to add a floppy drive to this box of mine ? 
> It has 2 SCSI controllers (that means no MFM controller i 
> guess .. but that would in term mean no MFM floppy -> RX23).

There are two ways. You can swap your SCSI-SCSI controller
for an older SCSI-FDD one and then a 3.5" floppy should
just work. Or you can get an RX23S (I think that's the
part number) which is basically a 3.5" floppy with a
SCSI interface.

> Last question: what's your experience with use of CD-ROM 
> drives in VS3100 ? Mine is KA42B, m38. Will its firmware be 
> able to deal with not-so-obsolete drive like Pioneer DR-U12X 
> for example ? The drive supports 512 byte blocks. If firmware 
> won't be able to cope with it will NetBSD be able to use it 
> regardless ? 

No idea. It should be easy enough to hook it up and see if the
firmware sees it at all. If it supports 512byte blocks, there's
a chance it will work. I've always had enough DEC CDROMs around
that I've never needed to hang anything else on a VAX.

Antonio
 
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Antonio Carlini             arcarlini@iee.org