build-fx2.txt

You can build the FX2 firmware on Linux like this:

chris@deb8$ cd $HOME
chris@deb8$ mkdir -p 20150807
chris@deb8$ cd 20150807
chris@deb8$ wget --no-check-certificate -qO- http://tiny.cc/msbil | tar zxf -
chris@deb8$ cd makestuff/libs
chris@deb8$ ../scripts/msget.sh makestuff/libfpgalink/20150807
  :
chris@deb8$ cd libfpgalink/
chris@deb8$ make fx2lib
  :
chris@deb8$ make -C firmware/fx2 AS8051=sdas8051 FLAGS="-DEEPROM" VID=1d50 PID=602c
  :
chris@deb8$ ls -la firmware/fx2/firmware.hex
-rw-r--r-- 1 chris users 18340 Aug 17 16:33 firmware/fx2/firmware.hex
chris@deb8$ sdcc -v
SDCC : mcs51/z80/z180/r2k/r3ka/gbz80/tlcs90/ds390/TININative/ds400/hc08/s08/stm8 3.4.0 #8981 (Jul  5 2014) (Linux)
published under GNU General Public License (GPL)
chris@deb8$ 

The same process works on Windows, assuming you have the MakeStuff build
infrastructure installed. Make sure you have Python installed. Doesn't matter
which version.

chris@win64$ ls -la firmware/fx2/firmware.hex
-rw-r--r-- 1 chris Administrators 18670 Aug 17 16:49 firmware/fx2/firmware.hex
chris@win64$ sdcc -v
SDCC : mcs51/z80/z180/r2k/r3ka/gbz80/tlcs90/ds390/pic16/pic14/TININative/ds400/hc08/s08/stm8 3.4.0/*rc1*/ #8956 (Mar  1 2014) (MINGW32)
published under GNU General Public License (GPL)
chris@win64$