That is, M function-the function used to instruct the machine tool auxiliary operation, that is, the instruction of the machine tool and its auxiliary device. Such as opening, stopping the cooling pump; the main axis of the main axis, stopping rotation; the end of the program, it consists of a two -digit number of M, a total of 100 species (M00 ～ M99). There is a division of modal (renewal) instructions and non -modular instructions. CNC knife management function: realize the management function of the geometric size and the life of the tool. The processing center should have this function, that is, the M function of the M, the function used to instruct the machine tool auxiliary operation, that is, the instruction of the controller and its auxiliary device. Such as opening, stopping the cooling pump; the main axis of the main axis, stopping rotation; the end of the program, it consists of a two -digit number of M, a total of 100 species (M00 ～ M99). There is a division of modal (renewal) instructions and non -modular instructions. CNC knife management function: realize the management function of the geometric size and the life of the tool. The processing center should have this function. The geometric size of the tool refers to the radius and length of the tool. These parameters are used for the compensation function of the tool; the life of the knife refers to the time and life of the time. Knife; in addition, the CNC system has T function, that is, the knife number management function, it is used to identify the tools and automatically select the tools in the knife library.