formatting MFM drives on a IBM PC

Chuck Guzis cclist at
Fri Sep 29 10:41:04 CDT 2017

On 09/29/2017 01:11 AM, Christian Corti via cctalk wrote:

> I don't consider writing servo information as lowlevel formatting.

I should have been more precise.  What I meant was "embedded servo".
Most, if not all,  modern drives use this technique rather than dedicate
a separate surface to servo.   There's no low-level format with this.
It's been around since at least the 1970s, but was slow to be adopted by
the PC drive manufacturers.  An interesting aside is that the Drivetec
floppy diskettes used embedded servo--which was why you had to purchase
them preformatted.

I recall visiting a friend at Tandon's "R&D" operation during the 80s.
The servo writer for the lab was an affair mounted on a granite block
and employed a laser for determining position.

At any rate, I hope this clears up what I meant.


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