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Re: 3.5 disk formatting



"Jon Co" <jon@i-manila.com> wrote in message
a2c2f792.0302030703.774f7c3a@posting.google.com">news:a2c2f792.0302030703.774f7c3a@posting.google.com...
> I know this is in the FAQ somewhere but I couldn't for the life of me
> find it when I need the answer.  What is the difference between 4:1
> and 2:1 formatting?  Copy II plus calls one high-speed format... which
> is which.  which is best for the apple 3.5 drive and which one is best
> for the unidisk 3.5?

The numbers refer to the interleaving of the sectors on a track.  How fast
either one is depends on how fast the system (drive, controller, & CPU) can
decode the data that it reads.  If the system can decode it fast enough to read
another sector after only skipping one sector then 2:1 is fastest.  If not then
4:1 is faster.  An Apple IIgs with an Apple 3.5" drive is faster with 2:1
formatting.  I believe a Unidisk on an Apple IIc is faster with 4:1 formatting
although I've never checked this.

Charlie