PCI floppy controller

[Chuck Guzis]

On 4/22/22 04:44, Liam Proven via cctalk wrote:

> The company did a range of parallel-port storage drives: CDs, tape
> drives and so on. Most were slow but worked, but the floppy drives
> were quite a good option at the time for things like laptops which
> couldn't accept another drive or controller, or for adding drives
> unsupported by the built-in controller. I used them for emergency
> backups, data transfer, data recovery and so on.

Back in the 90s, we bought these things by the carton, modified them to
work with Japanese DOS 2.0 format (PC98) 3.5" floppies, rewrote the
drivers, added a VxD for Win3.1 compatibility and sold a bunch of them.
 Popular with some segments of the CNC and other crowds.

If you check (very) old posts on VCFed, you may find the code I
published that provides a complete set of BIOS functions.  It
illustrates how the parallel link works, among other things.

Internals were pretty simple--a floppy drive (usually
Newtronics/Mitsumi), either an NSC 8374 FDC or later NSC 8477 FDC, an
8051-family MCU and about 16KB of SRAM and a small NVRAM chip to store
configuration information.

A not well-known fact is that the thing supports up to 4 drives and that
the configuration NVRAM stores not only the "ID" of the unit but also
the types of the 4 drives connected.

It's rare (and perhaps impossible) to find a real parallel port on a
modern system--usb parallel dongles don't work and neither do the PCIe
parallel port cards.   Along with the legacy floppy interface, the
legacy serial and parallel ports may have been the last vestiges of the
ISA architecture to be discarded.

--Chuck