Subject: re: HP 9144 driver
To: None <port-hp300@NetBSD.ORG,>
From: Mike Hibler <>
List: port-hp300
Date: 02/10/1996 19:21:39
> Date: Sat, 10 Feb 1996 18:10:06 -0600 (CST)
> From: Set <>
> To: port-hp300@NetBSD.ORG
> Subject: re: HP 9144 driver
> @> 
> @> 	Is anyone actually using the 'ct' driver in NetBSD 1.1? I
> @> recently hooked up a 9144 to an hp380 running 1.1, and was very
> @> quickly rewarded with a uninteruptible sleep from my tar...
> @> 
> 	I just hooked up my 9144a to my 1.1 system and it worked fine
> with tar. Dog slow, but it worked.... This was using a kernel I 
> built myself, with stock 1.1 source.
Note that there is a "streaming" device that we used to use to create
distribution tapes (this was in Utah's BSD, not 4.4 or NetBSD though it
shouldn't make a difference).  I believe we could only keep it streaming
with "dd" and a large (64k?) block size.  It was only semi-dog slow at that
point :-)

We used to use 9144 drives fairly regularly.  We always had two HP-IB busses
in every machine so we kept the tape on the slow (builtin) HP-IB and disks
on the "high-speed" (yeah, right...) interface.

An implementation note: the ct driver will hold on to the bus and one of the
two DMA channels during any operation.  So if you were doing a rewind from a
long way into the tape you would lock up that bus and potentially cut your
DMA throughput in half.