It moves in three directions x, y, z. The x direction moves the typewriter, the y direction moves the paper, the z direction controls ups and downs of pen.
To run, using ROBOTC for LEGO Mindstorms 4.X with the platform of EV3.(Of course first you need to construct a LEGO printer)
Open printer.c and download it to your EV3 controller. Then get start.
By the way, change the parameters like degrees that moters turns to fit your own LEGO printer.