I thought I'd drop y'all a line and let you know that I have gotten the
system to work (near as I can tell) with the 1542B.

It turns out that the SCSI terminaation power was to blame.

On the hard drives I am using, there are two settings for termination
power.  I had all three drives set to power the terminators from the
drive power.  Apparently, this didn't work.  I removed the jumpers from
the two unterminated drives, and the drive started to work better. 

I switched the terminated drive to power the terminators from the cable,
and the thing was off like a shot.

Now, if I could just figure out what all those "HOST_STAT 13"s mean when
I try to mount that Toshiba CD-ROM, I'd be all set.

Thanks to everyone for all the help.
-- 
Dave Burgess  (The man of a thousand E-Mail addresses)
386bsd FAQ Maintainer / SysAdmin for the NetBSD system in my spare bedroom
"Just because something is stupid doesn't mean that there isn't someone
that wants to do it...."