Drive inventory

From: Tothwolf <tothwolf_at_concentric.net>
Date: Thu Feb 14 13:31:40 2002

On Thu, 14 Feb 2002, Fred Cisin (XenoSoft) wrote:
> On Thu, 14 Feb 2002, Sellam Ismail wrote:
> >
> > > If you connect more than one tape drive to the floppy interface, they will
> > > conflict with each other. Even if you disconnect their power connector,
> > > but leave the data cable connected, you will have "weird" problems.
> >
> > Why?
> > Hmm, after thinking about this a little bit I can see that there might be
> > a conflict. But I would still like a technical answer to my "why"
> > question :)
>
> Drive Select.
>
> Add a switch to disconnect 10, 12, and 14. (DS0, DS1, DS2)
> Then you can leave the power on to the drive, but it will not be selected,
> and won't interfere with the others.
>
> Run all other signals through to all drives, but run the drive select
> lines through a switch to control which drive you want. Leave 14
> disconnected (most drives and software expect the drive to be #0 or #1),
> and get a 2P50T rotary switch?

That would work well if all the tape drives that use the floppy interface
followed the rules, but not all do. I guess it would be possible to build
a board with some logic chips that could isolate individual drives from
the bus, but I think it would be much easier for now to only connect one
drive at a time.

-Toth
Received on Thu Feb 14 2002 - 13:31:40 GMT