Yeah, the USB drivers are what scare me, but I'm always up for a challenge! -- Sincerely, James Burkart *Filmmaker & Documentarian* *Burkart Studios* 415.738.2071 | Phone 925.226.4910 | Fax *Web:* burkartstudios.com *Facebook:* facebook.com/burkartstudios On Fri, May 13, 2016 at 4:50 AM, James Cameron wrote: > If you think writing FAT filesystem driver would be difficult; I'd > give you about ten hours, maybe five. It is a surprisingly simple > format, easy to simulate and test. Given your use case of creating a > file and writing to it, the functionality required is much reduced. > > If you can read Forth, the Open Firmware filesystem driver is nicely > separated out into functional components. > > http://dev.laptop.org/git/users/quozl/openfirmware/tree/ofw/fs/fatfs > > On the other hand, if you mean writing USB drivers, yes, that can be > rather more fun! > > On Fri, May 13, 2016 at 04:25:38AM -0600, James Burkart wrote: > > Alan, your last suggestion would be ideal, only if it requires writing > > drivers from scratch then I am afraid it will be over my head, at least > for > > a while. > > > > -- > > Sincerely, > > > > James Burkart > > *Filmmaker & Documentarian* > > > > *Burkart Studios* > > 415.738.2071 | Phone > > 925.226.4910 | Fax > > > > *Web:* burkartstudios.com > > *Facebook:* facebook.com/burkartstudios > > > > On Fri, May 13, 2016 at 4:23 AM, wrote: > > > > > > This was in regard to possible speed issues when writing to an SD > card > > > over > > > > spi and an alternative to write to internal flash. > > > > > > > > If handling FAT is an obstacle, raw data can be written to the > memory and > > > > transferred with USB and sw in the PC which then writes to a file. > > > > > > > > If the device is battery operated, perhaps battery (or super cap) > backed > > > ram > > > > chips can be used as storage. Of course, data will be lost after a > > > certain time. > > > > > > If raw is going to be written I would suggest using an SPI or I2C FRA= M > > > chip instead of dealing with an SPI SD interface. Probably a lot > easier and > > > faster. > > > > > > On the other hand there is no reason that a FAT file system couldn't = be > > > set up on a suitably sized FRAM chip, and then accessed as a USB driv= e > for > > > downloading over a USB connection. > > > > > > -- > > > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > > > View/change your membership options at > > > http://mailman.mit.edu/mailman/listinfo/piclist > > > > > -- > > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > > View/change your membership options at > > http://mailman.mit.edu/mailman/listinfo/piclist > > -- > James Cameron > http://quozl.netrek.org/ > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .