On 02/04/2015 06:03 AM, GerardCJAT wrote:
For an OLD PC ( ISA slot ) obviously ....
Does this "beast" ever existed ??
Does anyone recall some manufacturer's name ??
Have I any chance to find one on Ebay or other at this time ??
Or is "DBIT" adapter the only way to go ?
Of course there were/are! All versions of the Microsoft Compaticard (I,
II, IV) have 8-inch support, though I'd recommend only the IV, since,
the I and II use a non-standard method of switching data rates.
Microsoultions even sold 34-to-50 position adapters.
And really, that's all that's needed--a wiring change. The CC manual
even includes a call-out for the change. I included a similar one in
the 22Disk documentation.
The Sysgen Omnibridge explicitly supported 8" drives and the new XT-FDC
project on Erik's Vintage Computer forum even features a 50-position
connector.
In fact, if your FDC supports single-density (FM) modulation and
high-density ("1.2M" and "1.44M" drive support), there's no reason
why
you need a separate floppy controller. You can download Dave
Dunfield's TestFDC program to test your system.
The DBIT widget is useful in that it includes an MCU that synthesizes
the RWC/TG43 signal that some 8" drives need for writing, but not all
do. Microsolutions supplies this signal via a separate latch on the CC.
--Chuck