SCSI cable question

[Dave Swegen <dave@recursive.prestel.co.uk>]

I just bought a 2nd hand SCSI scanner (it should work with linux), but
since I've never used SCSI devices in my life I'm not quite sure what I
need. 

The scanner has two ports: a 25 pin d-plug and a 50 pin centronics
port. The SCSI card I'm getting has a 50 pin centronics port. The cable
that came with the scanner has a 25-pin d-plug at either end.

One cause of confusion is that the manual doesn't actually say what the 25
pin port on the scanner is for, it only shows the cable being plugged into
the 50 pin port. Is it safe to assume that the 25 pin port is also for
SCSI?

Would it be enough to buy a 50-pin centronics -> 25-pin d-plug adapter? Or
would I have to buy a 50 pin -> 50 pin cable?

Also, the the scanner came with a 50 pin terminator. Does this go into
whatever device is at the end of the chain? Can I also attach internal
devices at the same time?

I'd be grateful if some kind soul could take pity on this SCSI-clueless
user...

Cheers
    Dave

-- 
         Dave Swegen           | Debian 2.1 on Linux i386 2.2.3
<dave@recursive.prestel.co.uk> | PGP key available on request
      <dsw@debian.org>         | Linux: The Choice of a GNU Generation
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