Running blinky demo on Spartan-3AN

HOWTO

First, add these two lines to /etc/udev/rules.d/10-local.rules (create the file if it doesn't
already exist):

ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="03eb", ATTR{idProduct}=="2ffa", GROUP="users", MODE="0660"
ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="1d50", ATTR{idProduct}=="602b", GROUP="users", MODE="0660"

...so you can talk to the relevant USB devices without sudo. Then connect your JTAG port to
your Minimus (TDO->PB3, TDI->PB2, TCK->PB1, TMS->PB0, +3.3V->VCC and GND->GND - keep the
connections short), and power up the board. No need to connect the USB cable to the FPGA board,
just the Minimus.

$ # Make sure you have your Xilinx ISE distribution added to ${PATH}:
$ echo $PATH | tr ':' '\n' | grep Xilinx
/opt/Xilinx/14.1/ISE_DS/ISE/bin/lin
$ which xst
/opt/Xilinx/14.1/ISE_DS/ISE/bin/lin/xst

$ # Make sure you've got the pre-requisites:
$ sudo apt-get install libusb-1.0-0-dev libreadline-dev dfu-programmer

$ # Fetch the proper firmware:
$ wget -q https://gist.github.com/makestuff/7414980/raw/408d24c3ef34e6f1ffcbe9936e47ac72bafa204e/minimus16.hex

$ # Put the Minimus in DFU mode (press HWB, press RESET, release HWB, release RESET), and:
$ dfu-programmer at90usb162 erase
$ dfu-programmer at90usb162 flash minimus16.hex
$ dfu-programmer at90usb162 reset
$ dfu-programmer at90usb162 reset

$ # Now fetch & build the tools and the "blinky" demo:
$ mkdir $HOME/20131101
$ cd $HOME/20131101
$ wget -qO- http://www.swaton.ukfsn.org/bin/makestuff-lindar-20130829.tar.gz | tar zxf -
$ cd makestuff/apps
$ ../scripts/msget.sh makestuff/flcli/20131101
$ cd flcli
$ make deps
$ cd ../..
$ scripts/msget.sh makestuff/hdlmake
$ echo dev > hdlmake/.branch 
$ cd hdlmake/apps
$ ../bin/hdlmake.py -g makestuff/blinky
$ cd makestuff/blinky/vhdl
$ ../../../../bin/hdlmake.py -t ../templates/null -b s3an-kit -p fpga

$ # Now query the JTAG-chain:
$ $HOME/20131101/makestuff/apps/flcli/lin.x64/rel/flcli -v 1D50:602B -q B3B2B0B1
Attempting to open connection to FPGALink device 1D50:602B...
The FPGALink device at 1D50:602B scanned its JTAG chain, yielding:
  0x01414093 <- You'll get something different here
  0x05045093 <- But there should nonetheless be TWO IDs found

$ # And finally program the FPGA:
$ $HOME/20131101/makestuff/apps/flcli/lin.x86/rel/flcli -v 1D50:602B -p J:B3B2B0B1:fpga.xsvf

At this point you should see the LEDs on your board blinking slowly.