3.5" floppy failure mode? Hub not attched to media.
mhs.stein at gmail.com
Sat Feb 28 18:00:54 CST 2015
----- Original Message -----
From: "Eric Smith" <spacewar at gmail.com>
To: "General Discussion: On-Topic and Off-Topic
Posts" <cctalk at classiccmp.org>
Sent: Saturday, February 28, 2015 5:56 PM
Subject: Re: 3.5" floppy failure mode? Hub not
attched to media.
> On Sat, Feb 28, 2015 at 11:14 AM, Mike Stein
> <mhs.stein at gmail.com> wrote:
>> Are you saying that it actually stepped in and
>> during a rotation to follow the eccentricity?
> Yes, it did fully closed-loop servo positioning,
> with embedded servo
> bursts in all inter-sector gaps. That's why they
> have not one, but TWO
> stepper motors for positioning, with a
> mechanical adder mechanism.
> The coarse positioning stepper doesn't have the
> resolution needed for
> track following.
> This can also be seen in their US patent
I knew they had two steppers but didn't know that
they could actually step every sector if
I'm convinced; pretty impressive, especially if it
was implemented on a 3.5" drive.
How much did these drives cost?
More information about the cctalk