Lpc2000

Hi,

Maybe it would be better for the file system structures but the data 
that was about to go on the media when the power failure happened is 
lost!
The idea of ALFAT chip is that you can EASILY share data between 
systems and your PC and the only choice is FAT as it is supported by 
almost any OS

Thanks,

Gus

--- In lpc2000@yahoogroups.com, Alaric Snell-Pym <alaric@s...> wrote:
> Gus wrote:
> > Hi,
> > 
> > ALFAT chip does save both FAT tables (if media is formatted with 
2 
> > tables) so if one got corrupted the second will be fine. I can't 
see 
> > how FAT can be a problem! If you lose power on ANY file system 
you 
> > will lose data. Simply close all open file handles and no data 
would 
> > be lost.
> 
> There are file system layouts that avoid that problem - 
transactional 
> ones, for example, tend to have a commit operation. If the power 
fails 
> before you commit, or during the commit, then when it comes back 
up the 
> filesystem is untouched - it was as it was at the end of the last 
> successful commit. Changes made since that commit are lost, yes, 
but 
> they weren't comitted, so the filesystem has not yet "promised" 
their 
> safekeeping, and the existing data is never mangled due to 
filesystem 
> inconsistency caused by the power failure.
> 
> Log-structured and journalling filesystems have this property - 
and log 
> structured file systems can be good for FLASH memory, too, since 
they 
> tend to spread writes out evenly!
> 
> However, they're not as widely supported as FAT, by any stretch of 
the 
> imagination. So good for local storage only, rather than 
interchange, in 
> general.
> 
> ABS
> 
> -- 
> Alaric Snell-Pym
> Work: http://www.snell-systems.co.uk/
> Play: http://www.snell-pym.org.uk/alaric/
> Blog: http://www.snell-pym.org.uk/categories/alaric/