LinuxCNC
From PROBOTIX :: wiki
http://www.linuxcnc.org/docs/html/common/Getting_EMC.html
http://www.linuxcnc.org/docs/html/quickstart/stepper_quickstart.html
http://www.linuxcnc.org/docs/html/config/stepconf.html
http://www.linuxcnc.org/docs/html/common/Stepper_Diagnostics.html