Subject: random hardware questions
To: None <>
From: Blaz Antonic <>
List: port-vax
Date: 05/04/2003 18:33:30

I finally decided to check out the guts of my VS3100 today (somebody
suggested that when i acquired it ... he said it would be "fun") and few
questions arose:

This is BA42A enclosure (formerly occupied by a VS3100/m76, as label

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 :)

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 ? 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 HD is RZ26L-W, made by Quantum. I can't find any info about this
drive via Google (tried "rz26l w quantum"), just a bunch of resellers.
Does anybody have any docs for this drive ? I'm curious as to what 'SP
sync' jumper is used for (it's open now); write protection i figured out
and 'spn dly' must be spin delay or something (the only one closed).
Does that 'SP sync' jumper affect the speed of the drive ? IIRC NetBSD
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 ? 

Is there some way to speed up that drive (apart from throwing it out the
window) ?
says it's a 5400 RPM drive with 0.5 MB of cache (!) and transfer rate of
32.8 MB/s (!!) but it feels slower than my old 130 MB 3600 or so rpm IDE
in 386SX/25 i used to have. WHile on topic of drive speed, is there some
method for drive benchmarking under NetBSD that would give results that
can be compared with other machines ?

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).

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 ? 

Blaz Antonic