Exabyte "on-line"

[Steve Dyer]

Well, as several people said, the Exabyte 8mm cartridge unit
works out of the box on the DECStation 3100 with Ultrix 3.1,
provided you have the dip switches set correctly (and possibly,
a late-model Exabyte with uptodate ROMs.)  For the record, my
dip switch settings as recommended by Exabyte tech support are:
(SW3 ON--even byte disconnect, SW4 ON--no busy enable,
SW5 ON--variable block mode on power up.)  Everything else is set to off.

I've been using it now for most of the evening, and I've
seen a few glitches which I'd like to compare with other
people's experience:

It's not clear to me how you get the unit to come "on line"
once you insert a tape.  Only with a power cycle after inserting
a new cartridge does the tape actually get threaded, and the
green LED indicate "on line".  Otherwise, if you insert a 8mm
cartridge (say, after removing an earlier one) the unit just
sits there offline.  I must be missing something.

"tar tbf 2 /dev/rmt1h ..." works fine.  "tar" with a blocksize
of 20 (10240 bytes) causes Ultrix 3.1 to hang completely.
I'm happy with the first, given that it works.  I am not
familiar with the optimum blocksize for an 8mm drive.
Is there one?  Do I end up losing a lot of tape with IRG's
if I'm not careful?



-- 
Steve Dyer
dyer at ursa-major.spdcc.com aka {ima,harvard,rayssd,linus,m2c}!spdcc!dyer
dyer at arktouros.mit.edu, dyer at hstbme.mit.edu