25 Jul
2010
25 Jul
'10
12:37 p.m.
On 25 Jul 2010 at 19:03, Tony Duell wrote:
Absolutely (as far as I know). Somebody mentioned the
FTDI chips that
essentially give you GPIO-like bit-level parallel I/O from a USB port,
you could probably use something like that -- with the appropriate
driver software o nthe hsot -- totalk to any device that was designed
to plug into a PC printer port.
A lot of parallel-printer-port devices use the 8 data lines only for
output, then use status lines as input on a nibble basis. I don't
know about using the FTDI to do that.
On the other hand, taking a commodity microcontroller and using it as
a USB device and thence to drive the parallel port is much less
expensive, particularly if you can get by with USB 1.1 speeds. The V-
USB project, for example, an open-source implementation for almost
any AVR uC.
I intend to do just that with the MicroSolutions Backpack drive,
which essentially uses NEC 765 FDC commands over the parallel port,
so access to all FDC registers is possible. The thing has a bit of
serial NVRAM (X2444 type) on board to hold floppy type information
and will handle 2 drives (and probably 4 with a few jumpers).
There was a fellow on eBay selling NOS Backpack floppy drives for
$0.99 each, so I picked up a bunch.
Years ago, I reverse-engineered the interface to these things, so I
have everything that I need.
--Chuck