The principle and control system of 3D printer is introduced. The tasks division and intercommunication technology of the 3D printer based on μC/OS II is mainly discussed. The 3D printing was divided into four tasks:touchscreen operation task,LCD display task,data generate task and print out task. Rely on the agile tasks intercommunicate ability of μC/OS II,the print data was sent from data generation task to print task by Mbox. In different tasks,the needed task is resumed and the unneeded tasks are hung u...