15 Sep
2006
15 Sep
'06
10:28 a.m.
Teo Zenios wrote:
I got an ebay find in the mail today, an external
floppy drive with a
port for another floppy. The odd thing about this drive is that the cable
going to it is 25 pin while the connector on the back for an additional
drive is the normal 23 pin variety.
That is odd. Did anything other than an external floppy drive ever use the
Amiga's floppy connector? If so, I wonder if they did it that way because the
25-way connector saved a bit of money, but they still wanted to present a
23-way connector to the 'outside world' for compatibility. Actually, didn't
the Amiga support four floppy drives anyway, so maybe the 23-way is there for
plugging in additional drives from other vendors...
I opened the case up and found a Citizen OSDC-45C drive which I believe is
a 720K DD drive along with a circuit board populated with a cap, some
other small caps, and 2 chips (Tesla MH7438 and HD 74LS74AP OL15).
I seem to remember building a little circuit many years ago to add a stock
PC-compatible 720K drive to the Amiga - much cheaper than buying a 'proper'
Amiga external drive! I seem to recall that being a couple of chips, one of
which was a LS74.
cheers
Jules