Subject: TK50 qbus funzies....(:+{{
To: None <port-vax@netbsd.org>
From: NetBSD Bob <nbsdbob@weedcon1.cropsci.ncsu.edu>
List: port-vax
Date: 05/29/2001 09:58:28
I was playing around with my BA123 box last night trying to write some
TK50 tapes, and ran into an interesting problem.  The machine had a
KA650 boardset with 32mb ram.  The TK50 would not write reliably at all.
It would barely read reliably from my master tapes.  I pulled the KA650
boardset and dropped in the original KA630 boardset.  The TK50 ran fine.
Is there something borderline about the quality of a BA123 backplane
running at 3 vups vs 1 vup?  I was wondering why I was having so much
problem with TK50 tapes lately, and it appears to be bus speed related.
In the early S100 days, we used passive bus terminator networks to
calm the bus a 4mhz.  I noticed that my 4000/200 has a bus terminator
card in it.  Should the BA123 have such a terminator board in it?
If so, which board, and where do I find one?  Any other suggestions
about TK50 bus speed related problems?

Thanks

Bob