fpga4fun.com

I recently bought a Digilent Nexys 2 board, and after a few days of research got to the point where I can successfully program it over USB from a Linux host without the use of a separate (and expensive!) JTAG interface. Google told me even before I purchased the board that this is a very common requirement; it seems that I'm not the only one interested in linux-hosted FPGA development. The pieces to make this work were all there, happily (see the README in the download below for details -- the chain of responsibility here is long); it just took work to assemble them correctly.

For those interested, I wrote a quick perl script to automate the process, available at: http://plausible.org/andy/nexys2prog.tar.gz

This wraps the multi-step mess (device detection/configuration, SVF generation, and JTAG download) as fully as possible, most importantly by doing the USB bus enumeration and dynamically reprogramming the Nexys 2 with a patched usb_jtag firmware blob in the script itself. The user just specifies the Xilinx bitstream file as the sole argument.

Installation is as simple as I could make it, requiring only Xilinx ISE, two binary packages (fxload and libftdi -- both available via apt-get on Ubuntu Intrepid) and one source install (UrJTAG -- just a simple "./configure;make;make install" will do).

Hopefully this will help other newbies with the learning curve. Let me know if something doesn't work, or if there are questions.

hi, I cant decompressed file Can you send the extracted file ? plz thnx

I downloaded nexys2prog.tar.gz today.
It turns out this file is not in gzip format, but it is in tar format,
so:

$ mv nexys2prog.tar.gz nexys2prog.tar
$ tar -xvf nexys2prog.tar

will extract the contents.