[Coco] high density floppy controller mods

[Robert Emery]

----- Original Message ----
From: jdaggett at gate.net
To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
Sent: Friday, August 4, 2006 9:37:37 PM
Subject: Re: [Coco] high density floppy controller mods


On 4 Aug 2006 at 11:33, Warren Hoslet wrote:

> The extra gaps required for the additional 18 sectors may make things
> pretty tight. Isn't that why PC disks went to 512 bytes per sector (to
> double the data bytes per-track without increasing the sector count)?
**************

All floppy contrrollers allow 128,  256, 512  and 1024 byte per sector. FAT12 is limited in its 
directory size. If you put enough small files on even a 3.5 in HD floppy, you can fill the 
directory tract before the data from the files fills the rest of the tracts. If my memory serves 
me correctly it had something to do with FAT12, if you keep the sectors per cluster the 
same, then you have more clusters per disk. This can create a condition where the sector 
usage becomes less efficient when storing large numbers of small files. The work around 
that was to increase the sector size and keep the same sectors per cluster.    

Going beyond 1.44 MB on a floppy is pushing the limits of the FAT12 directory structure. 

I would believes that as hard drives start to push closer to 1TB, FAT32 will likely become 
inadequate. Cluster sizes will have to grow  to a point that there will become a sizable 
percentage of wasted space on a formatted disk. 

james 


Where have you been? Fat32 has been basically outdated for years now. NTFS is the M$ standard if you expect any amount of file security at all, and yes, there is massive waste of available space. What any of this has to do with high density floppies on the CoCo, I don't know.
 
Bob