Find out inside. 5 ~ protoneer.co.nzOpensource CNC controller written for Arduino's ( G - code interpreter Opensource CNC controller written for Arduinos ( G code interpreter GRBL) Traditional CNC machines used old-fashioned printer / parallel ... 6 +1 reprap.orgArduino GCode Interpreter - RepRapWikiG - Code is a commonly use language to control CNC machines.