Floppy drive pin 2 question?

[Randy McLaughlin]

From: "Michael Sokolov" <msokolov at ivan.harhan.org>
Sent: Friday, March 11, 2005 12:25 PM
> Randy McLaughlin <cctalk at randy482.com> wrote:
>
> > I am 99.99% sure it changes the RPM, I have some TEAC 1.2's laying
around
> > I'll plug one in and ground pin 2 to check it.
> >
> > For the TEAC it is enabled via an option jumper, default is to ignore
it.
>
> Changing the RPM is an option on SOME drives, and for PeeCees to work it
> must be OFF.  It is very useful for Classic Computers, though.
>
> The high density select signal (pin 2) may or may not switch RPM, but it
> always switches the write current.  Writing on HD media with DD write
current
> will produce no effect (the field is too weak to affect the media), while
> writing on DD media with HD write current will magnetise the media so
> strongly that it'll be impossible to rewrite and unusable until you
> bulk-erase it.  So pin 2 MUST always select the correct write current for
> the media type.
>
> 3.5" drives use the media type hole instead to select the correct write
> current.  Those who punch or cover that hole to magically "change" the
> media type get what they deserve.
>
> MS

No, I have refered to the TEAC site and to WDC:

WDC referes to pin 2 as speed select, their controller can be used with
either single speed or dual speed 1.2mb drives:
http://www.wdc.com/en/library/legacy/controllerboards/1006mm1.pdf

TEAC specifically stated that pin 2 is default to ignore, the I strap is
used to enable speed change:
http://www.teac.com/DSPD/pdf/5fd0050a.pdf


Randy
www.s100-manuals.com