Subject: VAX 4000 scsi funzies.....
To: None <port-vax@netbsd.org>
From: BSD Bob the old greybeard BSD freak <bobkeys@weedcon1.cropsci.ncsu.edu>
List: port-vax
Date: 06/08/2001 11:26:28
I am building up my VAX 4000 BA213 crate, if luck is with me, this
weekend.  The original DSSI cable (the round cable) appears to be
a straight through 50-50 cable, except for a strange dual-key 
50 pin header connector on one end (probably put there so as not
to confuse with the ram connector on the cpu board).  But, I don't
care about that, since I am going to use a Qbus scsi card in it.
But, I would like to use the existing DSSI cabling (with suitable
mods) to run as the scsi cable off the scsi card.

1.  Other than the dual key funkiness of the DSSI cable, is there
    anything strange I should know ahead of time that might prevent
    its use as an ordinary scsi cable?

2.  The upper cabinet dssi ribbon cable that connects to the end of
    the round dssi cable looks like it will do for ordinary scsi.
    It has the DSSI HD50 connector on the end.  IS THAT CONNECTOR
    WIRED MATERIALLY DIFFERENT FROM ORDINARY HD50 scsi cabling?
    If so, how?
    
3.  What is the exact pinout of the normal scsi vs the dssi cable
    pinouts?  What I am hoping is that I can use that dssi ribbon
    and hopefuly its hd50 connector for the scsi output, so I don't
    have to materially hack up a centronics scsi plug onto it.
    That would be easy if that cable would sub correctly for HD50.

4.  Can I hang a DEC RRD42 or RRD43 cdrom drive on my hacked together
    scsi cabling and expect the KA660 cpu to boot the NetBSD-1.5 or
    maybe shortly-to-be NetBSD-1.5.1 boot cd images?  I am thinking
    so, but wanted to check, to be sure.

5.  Anyone got a spare VAX 3520 or 3540 scsi bus cable?  That one
    would do nicely for what I am trying to do, and I let my 3520
    box go to another VAX freak, so I can't use the one I had.

Anything else I should be aware of, ahead of time?

Thanks

Bob