I have ported the FPGA design into Spartan 3E and
working on making a simple interface for the Spartan 3A/3E
family of boards at the same time converting the code to
VHDL that is easier for me to understand and handle.
I will release the code into public by the end of
this year when we have finished all our internal testing, we
also working on a very low cost HW for GR that is a simple
USB stick and has almost the same HW as the USRP1 but with
external memory and extra options. Our goal is to make that
public in a few months and the selling price will be $299
I will be happy to share our pre-release of the FPGA
code with you if you are interested, this will be available
after September this year.