Re: Another dumb question...3.5" drives.

[dempson@actrix.gen.nz (David Empson)]

In article <37k6et$9u2@charm.magnus.acs.ohio-state.edu>,
Petar E Puskarich <ppuskari@magnus.acs.ohio-state.edu> wrote:
> 
> Hi there!  I KNOW I should KNOW this, but it is escaping me at this point.
> 
> Is it possible to have more than 2 3.5" apple drives on the smartport on the
> GS??????

No.  You can only have two Apple 3.5 Drives connected to the same
drive port, because there are only two drive enable signals.

Similarly, you can only have two 5.25" drives connected to the same
drive port.

Both of these types of drives are "dumb" when it comes to the drive
select signals.  The IWM drive select output is used directly.

More than two UniDisk 3.5 drives may be connected, because they use a
software addressing scheme.  In theory you could connect 126 UniDisk
3.5 or other intelligent SmartPort devices, but in practice you are
limited to four or six drives (in total), depending on the computer
and the drive connector.

You can also connect two Apple 3.5 drives and then one or more UniDisk
3.5 drives (and then one or two 5.25" drives, provided you don't exceed
the maximum number of drives on the port).

Another possibilty is to install an additional disk controller card
(e.g. the SuperDrive card).  You can then connect a further two Apple
3.5 Drives to that.

The SuperDrive is selected in the same manner as the Apple 3.5 Drive,
so you can only have two of them connected to the same disk port (or
one SuperDrive and one Apple 3.5 Drive).


I think that covers all the combinations.  :-)
-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand