Origin or 1.44 MV FD label [WAS: RE: Weekly Classic Computer Trivia Question (20141205)]

Fred Cisin cisin at xenosoft.com
Sun Dec 7 16:35:06 CST 2014

> > The disk is 1440 K, which is NOT 1.44M, it is 1.40625M,
> > or simply "1.4M".
> > Was it an ERROR?  Or the work of cheating assholes?

On Sun, 7 Dec 2014, Chuck Guzis wrote:
> Who's cheating?  The maker of your formatting program?  (Reaches over to
> the top of his PC and grabs a high-density 3.5" floppy)  I see three
> lines of writing on the shutter.
> Line 1: "IMATION"
> Line 2: "2HD"
> Line 3: "2.0 MB"
> And, as I pointed out, at the customary western high-density clock rate
> of 500KHz and 300 RPM rotation--and 8 bit bytes, comes out to exactly
> 2,000,000 bytes.
> Don't blame the manufacturer for getting less than you bargained for.
> It's very clear that "2.0 MB" means 2 x 10**6 bytes.

It makes sense for the diskette manufacturer to use unformatted capacity;
after all, they have no control of the format parameters.
Using Si units is disappointing, but not surprising.
And, it probably wasn't even Wabash that started that.

BUT, the creator of the FORMAT would have no excuse for using unformatted
capacity (NeXT), nor miscalculating it (IBM)

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