27 Apr
2013
27 Apr
'13
2:24 p.m.
On 04/27/2013 10:49 AM, Paul Birkel wrote:
All;
I'm curious as to what other manufacturers/systems supported the use of
block-oriented magnetic tape media along the lines of the DECtape (TU56)
and DECassette (TU60) drives.
You forgot TU58, 256K per drive x 2 drives using preformatted DC100 size
tapes.
In particular, what about the use of standard
1/2" tape media under such
circumstances? A wear-n-tear problem given the multi-pass nature of this
use (especially if being used to store temp-files for the OS), but if that
scenario were avoided ...
I'd like to play around with some, but acquiring either a DECtape or
DECassette unit looks to be somewhere between impossible and merely
seriously unaffordable -- not to mention obtaining media for use with
either. So I'm thinking about whether there are possibly other drives out
there for which I might construct a suitable controller to mediate between
the raw(er) mechanism and the OS.
Tu58s are around, the usual problem si dead capstan roller but they can be
remade easily using a peice of flexible plastic (Tygon) tubing.
Tapes can be found and the interface is serial line using a protocal for
commands and data packets.
There are TU58 emulators for PCs as well.
Unlike a streaming tape unit I'd expect that a major consideration would be
keeping the moment-of-inertia of the reels as low as possible, consistent
with holding a sufficiently long tape at sufficient bit-density to achieve
an economically-viable amount of storage per tape (*e.g*., 256Kb --
DECtape was 184K 12-bit words or 144K 18-bit words).
DEC managed it; did anyone else?
I'm certain there were many others but not any I tended to play with
being DEC based.
Allison