CD players, like the original Macintosh 390 K floppy disks, vary the angular velocity inversely with cylinder radius in order to have both uniform linear density and uniform data transfer rate.
Right. But floppies and CDs don't revolve at 3000rpm (or 7200rpm, whatever) like hard drives, so there are less inertial challenges to overcome when varying the angular velocity.
From: Paul Gilmartin <[EMAIL PROTECTED]> Reply-To: IBM Mainframe Discussion List <[email protected]> To: [email protected] Subject: Re: Track size and maximum single volume data set size Date: Thu, 12 Jul 2007 13:57:07 -0500 On Thu, 12 Jul 2007 14:34:17 -0400, J R wrote: >Well, I was always aware of the trade-offs, i.e. bit density >at the center v. bit density at the outside, but I wasn't >aware that anything was ever done about it with variable >data rates, etc. > CD players, like the original Macintosh 390 K floppy disks, vary the angular velocity inversely with cylinder radius in order to have both uniform linear density and uniform data transfer rate. -- gil
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