This control unit 50 includes a processor 51, memory 52, constituted by a ROM or RAM, a display 53, input means 54 such as a keyboard, an interface 55 to input or output a machining program or the like from or to external storage media, a motion control circuitry 56 for respective axes, an input/output circuit 57, and others, which are connected to the processor 51 through a bus 58.