Free FAT12/FAT16/FAT32 filesystem (C)
in [Embedded]
|
Prev: Sed1335 with LPC2294
Next: SD Card - boot sector
From: Donald on 9 Jan 2006 09:17 larwe wrote: > Markus Zingg wrote: > > >>Btw, Microsoft made FAT32 (and particularlly long filename support) >>available under a license. From what I understood the license is >>afordable for small projects but still a license... The intention - > > > The patents on which that was based were invalidated by the USPTO. > Do you have a link about this ?? donald
From: larwe on 9 Jan 2006 11:31 Donald wrote: > >>Btw, Microsoft made FAT32 (and particularlly long filename support) > >>available under a license. From what I understood the license is > > > > The patents on which that was based were invalidated by the USPTO. > > > Do you have a link about this ?? The easiest reference - because I'm lazy - is a mere mention <http://en.wikipedia.org/wiki/File_Allocation_Table> search for "October 6, 2005" In any case, the facts of the issue are: FAT32 per se contains nothing patented. The patents pertain to having multiple databases of filenames on the disk, i.e. LFNs in this case (which can be and are implemented on FAT12 and FAT16 also). The patents in question were re-examined and invalidated, so there is no longer anything to license. However Microsoft's licensing page for FAT "patents" is still a live link and I don't want to get involved in FUD and discussion. Of course the above argument is really specious and the real reason I don't implement LFNs is because I don't have any use for them in my application, and I'm lazy ;) Okay, I admitted it. I suspect the reason for the licensing program was more so that MS would be able to exert leverage on embedded device manufacturers to support MS formats or lose their "FAT license". The fee was $0.25 per device shipped, up to a cap of $150K (lifetime) per manufacturer, which is a peppercorn as far as MS is concerned.
From: "Sagaert Johan" <sagaert.j AT on 9 Jan 2006 11:57 have a look here http://sourceforge.net/projects/efsl "larwe" <zwsdotcom(a)gmail.com> wrote in message news:1136779531.250972.315290(a)g47g2000cwa.googlegroups.com... > Google Groups is being recalcitrant these past couple of days, so I > have no idea if the world will see this, but I've just released free C > source to my embedded FAT filesystem. I've tested this code on a > variety of platforms, including ARM, AVR and MSP430. > > I know there are several such filesystems in the world, but this one > meets my particular requirements for functionality vs. footprint - it > may be useful for someone else too. > > <http://www.zws.com/products/dosfs/> > > This code should be considered beta; I would appreciate feedback as to > bugs. > > Here's the abstract: > > DOSFS is a FAT-compatible filesystem intended for fairly low-end > embedded applications. It is not the leanest possible implementation > (the leanest FAT implementations operate in << 512 bytes of RAM, with > heavy restrictions). This code strikes a good balance between size and > functionality, with an emphasis on RAM footprint. > > Intended target systems would be in the ballpark of 1K RAM, 4K ROM or > more. > > Features: > > Supports FAT12, FAT16 and FAT32 volumes > Supports storage devices up to 2048Gbytes in size (LBA32) > Supports devices with or without MBRs (hard disks vs. floppy disks or > ZIP drives formatted as "big floppies") > Supports multiple partitions on disks with MBRs > Supports subdirectories > Can be operated with a single global 512-byte sector buffer > Fully reentrant code (assuming the underlying physical device driver is > reentrant and global sector buffers are not used). There are no global > variables in the filesystem > Does not perform any memory allocation > Partial support for random-access files >
From: larwe on 9 Jan 2006 15:23 Sagaert Johan wrote: > have a look here > > http://sourceforge.net/projects/efsl Unfortunately it tries to load an advertisement from ad.doubleclick.net (which is blocked by my anti-advertising software) and some Javascript or something on the page sees that the advertisement could not load, tries again, tries again, ... and locks the browser up hard. I'm not spending time on a site that's so determined to show me graphical spam. There is no advertising on zws.com :)
From: Jonathan Kirwan on 9 Jan 2006 18:26
On 9 Jan 2006 12:23:19 -0800, "larwe" <zwsdotcom(a)gmail.com> wrote: >Sagaert Johan wrote: >> have a look here >> >> http://sourceforge.net/projects/efsl > >Unfortunately it tries to load an advertisement from ad.doubleclick.net >(which is blocked by my anti-advertising software) and some Javascript >or something on the page sees that the advertisement could not load, >tries again, tries again, ... and locks the browser up hard. > >I'm not spending time on a site that's so determined to show me >graphical spam. Try Delorie's web site for viewing web sites with Lynx; http://www.delorie.com/web/lynxview.html and just type in the above address. Pleasingly absent of ads. Jon |