TK70 tape drive media?
pat at computer-refuge.org
Thu Jan 26 16:55:15 CST 2006
On Thursday 26 January 2006 17:33, Richard wrote:
> In article <200601262230.k0QMU7qR005246 at onyx.spiritone.com>,
> "Zane H. Healy" <healyzh at aracnet.com> writes:
> > > What do you use in this thing? I've got a VAX 4000/300 with a
> > > TK70, but it didn't come with any media and I'm wondering what I
> > > should be looking for to feed it :)
> > Compact Tape II's (aka TK70's :^)
> > Might be easier to find a TK50 drive, and controller, or get a
> > CD-ROM hooked in there. I have to question weather a TK70 is worth
> > the effort in this day and age, unless you're trying to *read*
> > tapes. Sadly, TK50's are still worth the trouble, at least on a
> > PDP-11.
> That's kinda what I figured. It looked like a weird DEC proprietary
> form factor for the media. A quick google didn't turn up any obvious
If by "proprietary DEC formfactor", you mean "looks like a DLT tape",
BTW, just any old DLT tape (probably) won't work in the drive. You need
to find a TK50 or TK70 cartridge. As Doc alluded to, you can maybe
possibly probably use bulk-erased TK50 tapes as if they were TK70
tapes, but it's a topic for a lot of disagreement... almost like "do
3.5" HD floppies work reliably as DD floppies?".
> discussion of the media. The machine has ethernet and I'm not sure,
> but it might also have a SCSI interface. With ethernet I can get
> data into/out of the machine (heck, even the console interface can do
> that, but ethernet would be more expedient).
Depending on what OS you run, you may want a real QBUS ethernet card.
I've had limited (read: horrible) luck using the onboard ethernet on my
4000/300 with NetBSD. I'm not sure if that's because of the controller
design, or whether my machine has issues. VMS might have better luck.
BTW, the male-HD50 "SCSI" connector on the 4000/300 is NOT SCSI, it's
DSSI, and while somewhat similar electrically, they're nowhere near
similar enough to be able to take a normal SCSI drive and connect it to
the bus. I tried that once, and ended up having to replace the
terminator fuses on the CPU. Also, NetBSD doesn't have DSSI support,
partly because DEC didn't do a very good job of documenting it, and
it's a fairly complex protocol, even compared to something like SCSI.
You might have a QBUS SCSI card though. KZQSA's are somewhat common on
the pedestal VAX 4000's for controlling a CDROM drive.... note that
while that works OK with VMS, it isn't supported as far as I know under
NetBSD, etc, and the interface was designed poorly enough that you
can't reliably run more than about 1 (or maybe 2) device(s) off of it.
You might also have a 3rd party SCSI controller, which *would* allow
you to connect SCSI disks to it, and be supported under more than just
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