This is a firmware for a RepRap 3D printer.

The original firmware was created by tonokip for the Arduino platform.
This firmware was ported to the mbed microcontroller platform.
It is running on my Prusa Mendel.

I use ReplicatorG to control the printer:
<driver name="reprap5d"> ... 57600 baud

You can use the .brd and .sch files in the Eagle_files subdirectory for a first PCB prototype. 
It can connect the mbed board to the Sparkfun Quadstepper Motor Driver board (sku: ROB-10507)
JP5 can connect a Sparkfun Thumb Joystick (sku: COM-09032)