28 Jan
2012
28 Jan
'12
3:40 p.m.
On 28 Jan 2012 at 15:07, Fred Cisin wrote:
MOST don't know what it stands for, nor the issues
involved in
non-standard ones. Remember how the discussion got side-tracked
into an assumption that the inverted data was the problem?
Sometimes, you just have to give step-by-step procedures. REPEATEDLY.
I guess you're right. I'll start by explaining which side of a
floppy is up--not so easy with users of early Altos boxes...
While it's true that the data on Superbrain floppies is
inverted/complemented, the remainder of the floppy is normal (i.e.
address marks, sector ID information, etc. is in the "normal" state.
Off the top of my head, the Columbia, Comupustar, M&K (Michels and
Kleberhoff), the Sharp MZ-80, and the Shelton systems also did it.
Actually, the Sharp MZ-80B also "inverted" the data in the sense that
side 0 is the top side of the floppy and side 1 the "bottom" side.
As far as "why?", I haven't a clue.
Sigh,
Chuck