"Floppy tape"

Mariusz Stanczak Mariusz at fbits.ttank.com
Tue Feb 19 19:16:36 AEST 1991


In article <1991Feb18.162005.15219 at sci.ccny.cuny.edu> jeffrey at sci.ccny.cuny.edu (Jeffrey L Bromberger) writes:

[description of "saw tape" deleted]

>I was working on this for a while, but gave up in disgust.  There was
>*no* documentation on the driver interface!  Even with a little help
>from some friends, it was still pretty ugly.  There was no
>*distributed* tp.h file, and the man page for qt(7) is positively not
>what we have - there were no working QIC-02 boards for the general
>public.

I was looking for that tp.h driver as well... what an "oversight" on
AT&T side ;-(  Does anyone have more on the faith of that piece of
information?


>What probably has to be done is to make a diffent kind of dbuf (maybe
>tbuf?) that stores huge data chunks.  If you can push enough
>data at the tape, you can get about a 6.5 second stream [...]

The largest -T I tried so far was 0.5MB, but even with `dbuf''s double
buffering `gtar' (and for that matter all other processes) seem to be
prevented from working when the tape does its "seeks" (the MeterMaid's
kernel line goes 100%), so this whole idea turns kind of flat (the point
would be to keep the thing streaming.  Then the resource use by the dri-
ver seems very low).  All these handicaps seem to go together with the
rest of the implementation (23MB out of a 60MB media?!?), and the culprit
looks to be the I/F board (or is there more to it?).  Anyways, looks like
another exciting (and very marketable ;-)) project for the 3B1 wizards-at-
-large, armed with the Technical-Docs-and-sources, and patience of us,
the-buyers-to-be.  Are you listening?  Can this thing be made to work
right?  BTW, How is the reliability of the device as it is, i.e. working
VERY hard?  All in all, I'll take it any day over floppies, if it doesn't
break too often.

-Mariusz
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