Re: drive 3.5 on Apple IIc

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

BluPhoenyx <bluphoenyx@earthlink.net> wrote:

> Guillaume Tello wrote:
> >     I have an Apple IIc with rom code '3'. I read that I can plug a 3.5
> > drive to it.
> > 
> >     I have this drive:
> >     Apple 3.5 Drive
> >     Model No A9M0106
> >     FCC ID BCG96AA9M0106
> >     P/N 825-1304-A
> >     Serial n� Y6C01MK
> > 
> >     Is it possible to use it?
> 
> I want to say no as I think that is the 'dumb' 3.5 drive otherwise known
> as a GS 3.5 drive.

I can confirm that part number. It works on the IIgs, IIc+, and on the
Mac 512KE, Mac Plus and several later models. If you have a Universal
Disk Controller card or Apple's "Superdrive" card, you can also use it
in an Apple IIe (and maybe a II+ for the UDC). It can also be connected
to a PC Transporter in a II+, IIe or IIgs.

IIc models with a ROM version number of 0, 3 or 4 only support the
UniDisk 3.5, which has a different part number and is quite rare.
(Searching... can't find it. Starts with A2M as it is only an Apple II
product, not an Apple II and Mac product.)

> >     Another question: on the back side of this drive, I can see another
> > connector. Is it to "chain" several similar drives?
> 
> It is for daisy chaining drives however you are limited as to how many
> you can chain. For the 2c I think it max's out at 2 3.5 and 1 5.25 at
> the end of the chain.

The IIc probably can't handle that many due to power supply limits. If
it can take three external drives then in theory all three could be a
UniDisk 3.5, as long as the slot 5 SmartPort firmware doesn't have an
artificial limit of two drives.

The IIgs can handle a maximum of four floppy drives on its connector.
There is a hardware limit of two Apple 3.5 Drives and two 5.25" drives,
but you could connect four UniDisk 3.5 drives to a IIgs (with no others
present).

> Yes, the 2nd 5.25 must be the last drive in the chain. I don't recall for
> sure but it's possible that some 2c's will limit you to 1 3.5 drive due to
> power supplied through the port. I also think the max number of 5.25
> drives 2.

Two 5.25" drives per slot. On the IIc, the built-in 5.25" drive is drive
1 and the external one is drive 2.

-- 
David Empson
dempson@actrix.gen.nz