MACHINE TOOL CONTROL METHOD

PURPOSE:To easily add new functions by storing fundamental functions of a working program in a ROM to operate a machine tool and transferring additional functions from an external storage medium to a RAM in an idle time of the operation. CONSTITUTION:Fundamental functions of a working program 3 such as parts related directly to operation of a machine tool 5 and setting display are stored in the ROM of a storage element 7. First, a CPU4 operates the machine tool 5 on a basis of the working program in the ROM, and next, the CPU4 uses the idle time during the operation to transfer additional functions such as optional functions and new functions from an external storage medium 1 like a magnetic disc to the RAM of the storage element 7. Thereafter, the CPU4 uses working programs in the ROM and the RAM to operate the machine tool 5. Thus, new functions are easily added, and the operation is started immediately after power-on.