3B2 memory, floppy drive

[Greg A. Woods]

In article <11033 at attcan.UUCP> ram at attcan.UUCP (Richard Meesters) writes:
> In article <860 at red12.qtp.ufl.edu>, taylor at qtp.ufl.edu (Charles Taylor) writes:
> >   1. Is the floppy drive that came standard on the machine a 360K or
> >      1.2 Mbyte floppy drive and which device do I use to address it
> >      as a 1.2 Mbyte drive? (if applicable).
> >
> The 3B2 line uses a 720K floppy drive, You must use 96tpi double or high
> density diskettes with this drive, and you are better off if you use the 
> high density media ( more reliability ).

Sorry Richard, but it's best if you DON'T try to use HD (high density)
diskettes.  If I remember right they have been specially formatted
during the manufacturing process in order to help the IBM PC/AT (and
compatible) drives to seek to the centre of the track (remember when
they cost $150 per box?  I sure do!).  This factory formatting is
quite difficult to erase, and in any case, I've had no luck trying to
use HD diskettes (when I was short of diskettes, I tried quite
desparately, on three different 3b2/400's, and on a 3b2/300 to format
some with no luck).

Your best bet for 3b2 floppy media is to use a known reliable brand of
DS/DD (48tpi) diskettes (because they are cheap and easily available),
and always format with error checking and write with verify.  All
diskette media comes from the same cookie cutter.  The label
identifies the degree to which it was tested.  Some manufactures
downgrade the rating of cookies which fail the more stringent tests,
and others simply junk the cookie.
-- 
						Greg A. Woods

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