Emulex TC7000 -- "rewind hang"

[acheng at uiucdcs.UUCP]

>/* Written  3:45 pm  Jan 28, 1985 by karl at cygnet in uiucdcs:net.unix-wizar */
>/* ---------- "Emulex TC7000 -- "rewind hang"" ---------- */
>
>There have been at least two postings regarding a problem with
>Emulex's TC7000 tape controller.  When rewinding, the VAX "hangs"
>-- nothing else happens until the tape gets back to Load Point.
>...
>The fix is to get a PROM upgrade from Emulex.  We went from Rev. C
>to Rev. F this weekend and that solved the problem.  I don't know 
>anything about other revision levels.  I also don't know why Emulex
>ships cards with back level PROMs... this was a new card for us.

We have installed a Kennedy 9400 tridensity tape port on our 750 with
the TC7000 too.  We got the same rewind problems with same PROM solutions.
But we also installed another 9400 on our Pyramid 90x using their interface
board (what i don't know).  It has the similar rewind problem but Pyramid
has not figured out a solution.  I am wondering if Emulex and Pyramid got
the boards from the same vendor/design.

>...
>We still have two outstanding problems:
>
>	1. The Cipher does not stream at 6250 BPI.
>	2. We cannot select the density with software (i.e.
>	   varying the minor device number has no effect).

I read through our version of the TC7000 document, somewhere in a "hidden"
page it says the TC7000 works for VAX 750 only, not 780 yet.  Don't know
if this helps.  However, we are using the 4.2 distributed ht.c to drive
the tape and are able to remotely access the tape by 6250 or 1600 bpi.
The ht.c can access a high/low densities and we set up the 9400 tape port
to switch between 6250/1600.  We figured that if we really want the 800 bpi,
it can be manually set.  Hope the above helps a bit.

			albert cheng
			acheng at uiuc.ARPA
			ihnp4!uiucdcs!acheng