16 Jan
2005
16 Jan
'05
5:23 a.m.
On Sun, 16 Jan 2005, Scott Stevens wrote:
The original IBM-PC's floppy controller made
provisions for four floppy
drives. There are control lines to select up to four drives on the
single interface. They put a 37-pin D-shape connector on the bracket of
early IBM floppy controller cards so you could plug in an expansion case
with two external floppy drives.
I only did this once, as an experiment, to see if I could run my old
WWIV BBS on floppy-drives only, to reduce the noise of the machine. (It
worked, but was much slower.)
I'm pretty sure the 'fix' isn't to plug in an old IBM controller,
though, unless you're already talking about a vintage restoration
project. But the third and fourth select lines should be available on
some controllers.
I'd like to make a box with four floppy types: 5.25" 360 and 1.2, and
3.5" 720 and 1.44. I seem to recall someone here did this.
I imagine I can use the integrated floppy controller and then add another
board to provide the additional controller.
I'll check the DOS manual to see if it says anything as Nico indicates.
--
Sellam Ismail Vintage Computer Festival
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