25 Jun
2013
25 Jun
'13
8:55 a.m.
On 6/25/13 8:01 AM, Mr Ian Primus wrote:
--- On Tue, 6/25/13, Alexandre Souza
<alexandre.tabajara at gmail.com> wrote:
I uploaded a document to http://bitsavers.org/pdf/apple/disk/sony/ that describes
the differences in pinout.
I **BELIEVE** I can use
the 800K or 1.44MB internal drives from macs into the 19 pin
port of the IIgs. After all, is the same IWM the old macs
use.
Yes. You can. You can use any of the auto inject drives from a Macintosh, connected to
that 19 pin port on the back. The 800k mechanism in the external 3.5" drive is
exactly the same as the one in a Mac. And you can swap the mechanism in an external drive
with a Superdrive and it will work with the IIgs as 800K, it just won't work as a
Superdrive unless you have the (very rare) Superdrive controller for the IIgs.
The eject button on the external drive is connected to the little board in the external
drive enclosure with the daisy chain connector on it. I don't remember the specifics
of that board off the top of my head, unfortunately.
I forget exactly how drive select is done on the 3.5 drives, but I know on the Unidisk
5.25, there are two pins for drive select. 9 and 17, IIRC. 17 selects the first drive, 9
selects the second, and 9 on the first drive is routed to 17 on the daisy chain connector
for the second. I think there's an additional pin for 3.5 enable. Hence why you have
to have the 3.5" drives first in the chain, before the 5.25's.
-Ian