[Hidden-tech] More packrat stuff... files off an ms-dos system?

[Robert Heller]

At Thu, 12 Jun 2008 10:15:17 -0400 ussailis at shaysnet.com wrote:

> 
>    ** The author of this post was a Good Dobee.
>    ** You too can help the group
>    ** Fill out the survey/skills inventory in the member's area.
>    ** If you did, we all thank you.
> 
> 
> Moons ago (perhaps in '97) I acquired a box of 500 1.44 floppies with AOL
> V2.5, for $10. Almost gone now. Yet, I still recycle them, even using one
> Monday for a spread-sheet back-up.
> 
> I believe that 1.44 floppies will work just fine in a 720K drive. And
> perhaps the other way around. There was a lot of BS during the "floppy
> wars" about this. One of the improvements had to do with the precision with
> which the lead screw in the drive was made, and had nothing to do with the
> media at all. 

Yes, a 1.44M drive can read and write a 720K floppy (at 720K or 640K). I
don't know if 720K floppy media can in fact be low-level formatted to
1.44M or not or if the drive will let you even try -- I think the
floppies have different 'holes' at the back that the drive uses to sense
media type (as well as write-protect).

A 720K/640K drive can handle a 1.44M floppy, but probably at 720K/640K
-- this is mainly a function of the driver cirtuitry (not quite
'firmware' since floppy drives use pretty much hardwired logic rather
than a microcontroller). The difference is bit density (and data rate)
-- both 720K/640K and 1.44M floppies all have 80 tracks/side.  The
1.44M have twice the bit density.  Bit density relates to the heads'
geometry and field strength and how much field strength is needed by
the media to record a bit and the quality of the media (eg its dropout
rate / how dense the magnetic particles are).


-- 
Robert Heller             -- Get the Deepwoods Software FireFox Toolbar!
Deepwoods Software        -- Linux Installation and Administration
http://www.deepsoft.com/  -- Web Hosting, with CGI and Database
heller at deepsoft.com       -- Contract Programming: C/C++, Tcl/Tk