ian@sibyl.eleceng.ua.OZ (Ian Dall) (03/03/91)
We are getting a DecStation 5xxx (not sure which one here) but it
hasn't arrived yet so I can't "look and see" what comes as standard in
Ultrix. I want to put a QIC-24 compatable SCSI interface tape drive on
the system. In the future we might want to put other 3rd party SCSI
devices on it.
What I want to know, is whether Ultrix device drivers allow this. On
at least one other SCSI based system I know of, the minor device no.
is mapped into SCSI unit numbers so that adding a new tape is just a
matter of mknod'ing the correct entry in /dev. We will have one (non
QIC-24) DEC tape drive so a tape driver will be there.
How difficult is it to add new device drivers? Is the interface
between the SCSI interface and the tape and disk drivers well defined?
Is source for the device drivers supplied?
--
Ian Dall I'm not into isms, but hedonism is the most
harmless I can think of. -- Phillip Adams
ACSnet: ian@sibyl.eleceng.ua.oz
internet: ian@sibyl.eleceng.ua.oz.aufrank@croton.nyo.dec.com (Frank Wortner) (03/05/91)
In article <897@sibyl.eleceng.ua.OZ>, ian@sibyl.eleceng.ua.OZ (Ian Dall) writes: > I want to put a QIC-24 compatable SCSI interface tape drive on > the system. In the future we might want to put other 3rd party SCSI > devices on it. > > How difficult is it to add new device drivers? Is the interface > between the SCSI interface and the tape and disk drivers well defined? > Is source for the device drivers supplied? When you get your machine, take a look in /sys/data/scsi_data.c. There's a large comment in there with general instructions for adding devices. I'm not sure about availability in OZ, but here in the US Digital sells a QIC tape drive called the TZK10. If you don't have a QIC drive already, you might want to check it out. Frank
pavlov@canisius.UUCP (Greg Pavlov) (03/06/91)
In article <897@sibyl.eleceng.ua.OZ>, ian@sibyl.eleceng.ua.OZ (Ian Dall) writes: > We are getting a DecStation 5xxx (not sure which one here) but it > hasn't arrived yet so I can't "look and see" what comes as standard in > Ultrix. I want to put a QIC-24 compatable SCSI interface tape drive on > the system. In the future we might want to put other 3rd party SCSI > devices on it. > > What I want to know, is whether Ultrix device drivers allow this. We, like many others, use 3rd party disks on DEC 5000s (HP and Seagate). We also use an AVIV/Exabyte 8mm tape drive. Non required acquisition/ installation of special device drivers. In general, you should be able to do the same. But I would insist on "references" of current users before purchasing any third-party hardware; there's enough on the market that should allow you to insist on this condition and still obtain what you need. greg pavlov, fstrf, amherst, ny pavlov@stewart.fstrf.org
mwp@ubeaut.enet.dec.com (Michael Paddon) (03/08/91)
From article <897@sibyl.eleceng.ua.OZ>, by ian@sibyl.eleceng.ua.OZ (Ian Dall): > We are getting a DecStation 5xxx (not sure which one here) but it > hasn't arrived yet so I can't "look and see" what comes as standard in > Ultrix. I want to put a QIC-24 compatable SCSI interface tape drive on > the system. In the future we might want to put other 3rd party SCSI > devices on it. > > What I want to know, is whether Ultrix device drivers allow this. On > at least one other SCSI based system I know of, the minor device no. > is mapped into SCSI unit numbers so that adding a new tape is just a > matter of mknod'ing the correct entry in /dev. We will have one (non > QIC-24) DEC tape drive so a tape driver will be there. > > How difficult is it to add new device drivers? Is the interface > between the SCSI interface and the tape and disk drivers well defined? > Is source for the device drivers supplied? There is a SCSI tape driver included in Ultrix 4.X. To allow the use of a tape drive with SCSI address 'X', you must configure a kernel with the line looking like this in the config file: tape tzX at asc0 drive X (at least that's true for my DS5000). Then all you have to do is mknod (or better yet use MAKEDEV, which knows which major/minor numbers to use) the correct entry in /dev. However, there is one slight problem... Not all SCSI tape drives are created equal. You may have to add an entry to the tape_opt_tab table in /usr/sys/io/scsi/mips/scsireg.h to describe the capabilities and SCSI parameters of your particular drive. There is a fairly detailed comment in that file explaining exactly how to do this. In general, new drivers are as easy to add to Ultrix 4.X as they have ever been (ie. straightforward so long as you know what you are doing). Of course, you don't need to add a new driver for SCSI tape or disk -- they are already there. Finally, source to these drivers is *not* supplied, but you can do substantial tweaking via include files. Michael ------------------------------------------------------------------- | | Internet: paddon@meo78b.enet.dec.com | | Michael Paddon | ACSnet: mwp@ubeaut.oz.au | | | ACSnet: mwp@munnari.oz.au | | | Voice: +61 3 895 9392 | -------------------------------------------------------------------