Path: utzoo!utgpu!water!watmath!clyde!att!ucbvax!husc6!cfa!ward
From: ward@cfa.harvard.EDU (Steve Ward)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Adding 3.5" Floppy, (Need Help)
Summary: 3.5 inch floppies
Message-ID: <1064@cfa.cfa.harvard.EDU>
Date: 14 Jul 88 22:48:14 GMT
References: <15000054@silver> <47200008@hcx1> <879@netxcom.UUCP>
Organization: Harvard-Smithsonian Ctr. for Astrophysics
Lines: 32


3.5 inch floppies have the following general features:

720K formatted version:
----------------------

80 tracks/side
2 heads
160 tracks, both sides
@512bytes/sector, 8 or 9 sectors/track (9 for MSDOS)
250KBPS transfer rate -- same as 5" 360K floppy
head step rates and settling times are generally faster than
5" floppies

1.44MB formatted version:
------------------------

80 tracks/side
2 heads
160 tracks, both sides
@512 bytes/sector, 16-18 sectors/track (18 for MSDOS)
500KBPS transfer ratte -- same as 5" 1.2MB floppy
head step rates and settling times are generally faster
than most 5" floppies

3.5" floppies shouldn't run slower than their 5" counterpart if
the same device driver is used for both.  With a different driver
there may be built-in step/settle delays or other code differences
that inflict a noticeable speed difference, at least when doing
simple single file or directory listings or even formatting.

SMW