The IWM in it's original rendition is the Disk ][ Controller cards'
descrete logic combined to a single IC.
The IWM contains no firmware. Thus it is not a SmartPort.
The original //c is a good indicator of this as it does not itself
contain a SmartPort until the addition of the UniDisk compatible ROM
upgrade.
This card;
http://apple2.org/images/InterfaceCards/images/Hard.FloppyDisk/image-html/IWMDiskIICTRLr.html
Is the equiv. of the original //c release. As you can see it's just an
IWM, the 6309 PROM and the typical 245.
The Liron card is the SmartPort equiv. on a card.
http://apple2.org/images/InterfaceCards/images/Hard.FloppyDisk/image-html/UniDisk_Liron35.html
As you see here, this card contains the IWM, 245 and other descrete
logic, mainly in support of the onboard ROM, but also to supply some
status and toggle points.
This card will support the Apple Smartport 3.5" product line, (Uni and
Duo*)
http://www.apple2.org/images/DiskDrives%26Related/DuoDisk3.5.JPEG
http://www.apple2.org/images/DiskDrives%26Related/DuoDisk3.JPEG
Build your own DuoDisk 3.5 - Just add the missing stuff.
http://www.apple2.org/images/DiskDrives%26RelatedLironLogic.JPEG
.... in an ironic about face:
The 5.25" product line at the time of the great storage product merge
for the Apple product line was a single device and two of them would
have been two of them stacked/chained.
http://www.apple2.org/images/DiskDrives%26RelatedUniDisk5-25Take1.JPEG
But Apple ended up combining two 5.25" devices into one cabinet. I
guess this //e stack with a Monitor // was just too inviting.
But look at the 3.5" concept, one or two were a single cabinet. The
stuff was prototyped opposite than the actual release options.
The idea here was to use the same drive on the ][ and /// line using
the proper host cable, the A2 being 19 pin, the /// being 25 pin. The
FileWare floppy (Twiggy) was slated for a 25 pin external version for
the /// as well.
Anyhow, the Liron card can also connect to the Chinook SmartPort hard
drive and ProAPP External drive series. Another one is the Quark QC-10.
In rare instances, the Apple HD 20 (ProFile 20) also worked with the
Liron card.
In the end, the only thing Apple marketed for the Liron card was the
UniDisk 3.5. DuoDisk 3.5" never made it to market. Want dual? Buy two.
A stab at the Mac was that the Apple II supported 800K first, for a
full 6 months before the Mac 512Ke/Mac Plus.
Anyhow;
Here is a 4 drive card-
http://apple2.org/images/InterfaceCards/images/Hard.FloppyDisk/image-html/Concorde4DriveCTRL.html
Another one;
http://apple2.org/images/InterfaceCards/images/Hard.FloppyDisk/image-html/Rana4DriveCTRL.html
These patched the DOS 3.3 image in RAM with a preboot disk and then you
initialized a disk and the mod stays.
The usual way of hackng these was to use the Volume #. The alternate
way was to actually do ,D3, D4.. if you patched DOS 3.3 halfway for the
,D patch you could do even and odd drive #s all the way to 255 and if
you had a Disk ][ controller in there the odds would spin drive 1, the
evens would spin drive 2.
Thats a whole topic in and of itself, but the gist of it basically is,
the hardware unless a whole lot more is added, as you can see- supports
two 5.25" drives and this is not a SmartPort function. There is only
one drive select line on the 19/20 pin card. High or low, drive one or
two. With regards to 5.25" drives.