[comp.sys.mac.hardware] Internal Drives question

user7@amdcad.AMD.COM (Unix class) (11/29/89)

Are there any  differences between 800K disk drives for different computers?  Can
you use 800K disk drives from an SE on a PLUS and vice versa?
can you use an external drive as an internal drive without the casing?
thanks.
			-CHUNG

xdab@tank.uchicago.edu (David Baird) (12/03/89)

In article <28171@amdcad.AMD.COM> user7@amdcad.UUCP (Unix class) writes:
>
>Are there any  differences between 800K disk drives for different computers?  Can
>you use 800K disk drives from an SE on a PLUS and vice versa?
>can you use an external drive as an internal drive without the casing?
>thanks.
>			-CHUNG

I am unable to answer your last question, but regarding the first, there
are no differences between a Mac Plus and a SE when it comes to 800k disks.
You can also use the 800k disks with all the flavors of Mac IIs.

	David Baird

gordon@cs.washington.edu (Gordon Davisson) (12/08/89)

In article <28171@amdcad.AMD.COM> user7@amdcad.UUCP (Unix class) writes:
>
>Are there any  differences between 800K disk drives for different computers?
>Can you use 800K disk drives from an SE on a PLUS and vice versa?

There are differences, but they're minor.  Apple has used two versions
of the internal 800K drive (well, there may be more, but I haven't
noticed the differences).  The early version can be plugged directly
(20-conductor ribbon cable, wired straight through) into a classic Mac
(128/512/Plus), and the later version can be similarly used on an SE.
Using a later version drive on a classic Mac will make the eject motor
run continuously unless a special cable (missing conductors 9 and 20,
if I remember right) is used.  Apple used this combination, and had
some special ribbon cables made with these two conductors missing (i.e.
there's solid plastic where the wire would normally be).  You can tell
these cables because conductor 1 is painted yellow (rather than red).
I'm not sure about putting an early version in an SE, but I think it
should work directly.

>can you use an external drive as an internal drive without the casing?

Yes, provided you have a mounting bracket, and it's not one of those
weird Apple IIgs (I think it is) external drives that're also sometimes
used with Macs.

--
Gordon Davisson
Westwind Computing	(206) 632-8141
4518 University Way NE, Suite 313, Seattle WA 98105