I have got a problem designing my little uC-Project:

I am building up a small µC Board which can read in Audio Data. If I want to avoid Jitter effects I should do this in equidistant steps.

To use ethernet, SD card, USB, ... without having to write the drivers by myself it seems advicable to use an existing linux distribution.

But are there any distibutions which work on a "stand-alone" AT91SAM, I mean with no Standard development board around it?

Has anybody worked with qnx (which seems to be free to use for noncommercial customers)?
How do I install this linux? Put it on SDCard and let the AT91 boot from it?
Is there any installation kit for Windows / Linux which can create such a bootdisk?

Sincerelly,
Dirk