16 Jan
2006
16 Jan
'06
9:10 a.m.
Do you want to see my 9-track HP 7970B with 200, 556 and 800 bpi
densities?
--
Not necessary. I have two.
If you look at the 7970B manual, there is a configuration
matrix which shows that the only HP drive which supported
sub 800 bpi densities and 9 track tapes is a read-only
drive with dual 7 and 9 track head stacks.
What would be more interesting is if you could find any
place in the ANSI standards documenting a sub 800 bpi
9 track 1/2" tape format.
800bpi 9 track was invented by IBM for System 360,
which went from 6 to 8 bit character encodings.
There would have been no reason to support lower densities
on these drives, since all of the previous IBM tape drives
were 7 track.