AVR-Chat

Hi Gus, 

> -----Original Message-----
> From: Gus [mailto:gus_is_working@yahoo.com] 
> Sent: 21 July 2005 19:29
> To: AVR-Chat@yahoogroups.com
> Subject: [AVR-Chat] Re: readin USB thumb drive and USB keyboards
> 
> a reliable FAT 12,16 and 32 with read and write is a lot of 
> code. I don't what you are talking about but with our 
> optomized code it is about 50K flash and 5K RAM

I'd have to agree that a reliable FAT12/FAT16 implementation is rather
more complex that a simple read-only-from-top-level-directory file
system.  Do you implement VFAT too, so long filenames are supported?
That's something I have yet to implement and it really, really doesn't
look at all pleasant!

I'd also say that Microsoft have a document that covers how FAT works
but when you come to interoperate FAT with different operating systems
you find other nasty surprises thrown at you that are at odds with the
specification.  Just try using a FAT-formatted volume with one FAT
(rather than the usual two) with some FAT libraries and you find just
how badly code can be written and left untested.

--
Paul Curtis, Rowley Associates Ltd  http://www.rowley.co.uk
CrossWorks for MSP430, ARM, AVR and now MAXQ processors

no long file name support. As this is used for embedded systems, we 
never got any request for long file name support

Gus
--- In AVR-Chat@yahoogroups.com, "Paul Curtis" <plc@r...> wrote:
> Hi Gus, 
> 
> > -----Original Message-----
> > From: Gus [mailto:gus_is_working@y...] 
> > Sent: 21 July 2005 19:29
> > To: AVR-Chat@yahoogroups.com
> > Subject: [AVR-Chat] Re: readin USB thumb drive and USB keyboards
> > 
> > a reliable FAT 12,16 and 32 with read and write is a lot of 
> > code. I don't what you are talking about but with our 
> > optomized code it is about 50K flash and 5K RAM
> 
> I'd have to agree that a reliable FAT12/FAT16 implementation is 
rather
> more complex that a simple read-only-from-top-level-directory file
> system.  Do you implement VFAT too, so long filenames are 
supported?
> That's something I have yet to implement and it really, really 
doesn't
> look at all pleasant!
> 
> I'd also say that Microsoft have a document that covers how FAT 
works
> but when you come to interoperate FAT with different operating 
systems
> you find other nasty surprises thrown at you that are at odds with 
the
> specification.  Just try using a FAT-formatted volume with one FAT
> (rather than the usual two) with some FAT libraries and you find 
just

> how badly code can be written and left untested.
> 
> --
> Paul Curtis, Rowley Associates Ltd  http://www.rowley.co.uk
> CrossWorks for MSP430, ARM, AVR and now MAXQ processors