DD disks and HD drives (was: Where can I find...)

From: Eric J. Korpela <korpela_at_ellie.ssl.berkeley.edu>
Date: Mon Jun 26 11:30:55 2000

> On Sat, 24 Jun 2000, Tony Duell wrote:
> > DD drives or that DD disks can be used in HD drives _as HD disks_ (most
> > HD drives can also handle DD disks, but only to store the amount of data
> > that you'd get from a DD drive anyway).
>
> One word of caution regarding the use of DD disks in HD drives: it's
> been my experience that which this may appear to work, problems
> sometimes arise when one attempts to read the data written in a DD disk
> by an HD drive.

If IBM had only chosen to use a real double density format. (Note that your
DS/DD disks say 96 tpi on them.) Most serious buisness CP/M systems of the
era had an 80 track double density format, not this 40 track IBM cr*p. What
really annoys me is that IBM and MS never rectified the problem, and even
after we all had 96 tpi drives, we still couldn't put 720k on a DS/DD disk
without special software. (Unless we happened to have one of the few MS-DOS
machines that supported the format like Tandy, Victor, and Epson if you wanted
to pay the exhorbitant price they charged for a compatible 96 tpi drive.)

Having a 5.25 double density format that held nearly the same as a 3.5 double
density drive would have greatly sped the acceptance of 3.5 inch drives on
IBM compatble machines.

Eric
Received on Mon Jun 26 2000 - 11:30:55 BST