"The Hard Disk You've Been Waiting For"

[Steven Hirsch]

On Tue, 27 Apr 2010, Chuck Guzis wrote:

> On 27 Apr 2010 at 20:53, Steve Maddison wrote:
>
>> It would be interesting, but I'd guess the average file size at the
>> time that disk came out was significantly more then ten bytes!
>
> Consider the time and the target audience (S100 users).  Most
> probably running some flavor of CP/M.  So you're dealing with a
> "flat" file system with a fixed number of directory slots (512 was
> common for hard disks; a large file was broken into "extents", with
> each extent occupying its own slot).  So there was a finite limit to
> the number of files that could be placed on such a device.
>
> I seem to recall also that the official CP/M volume size lmitation
> was somewhere around 8 MB.  Not as restrictive as, say, the Apple II
> scheme of making a (IMI?) hard disk look like 50 floppies, but there
> are limits.

It would be the original Corvus "flat cable" drive with that silly 
partitioning.  They also did that for Atari 800, TRS-80 and a few others. 
Later on they patched Apple DOS to recognize much larger volumes.

> At about the same time we were deploying 7 and 14 MB Rodime 5.25"
> drives, I remember that we received a sample drive from Evotek that
> was something like 50MB (had a plexiglas HDA cover, so that was kind
> of cool to watch).   I don't think I ever saw that drive sold.  I
> stilll have the documentation somewhere.

The 8" IMI drive in one of my older Corvus drives has a clear plexi cover 
as does the Fujitsu 8" unit I'm wrestling with currently.  Seemed to be a 
popular design for the larger form-factor units.  I guess they figured if 
you're paying $5k for a drive you should be able to watch it work :-).

Steve


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