DECIDING METHOD FOR CUTOFF OF PROGRAM EXECUTION

PURPOSE:To prevent a program from being stolen without restricting copy by recording an identification (ID) number checking program in plural positions of a program area and detecting the coincidence of the number by a sending request means and a receiving means. CONSTITUTION:The addresses of an ID number storing circuit 7 in which ID numbers are previously stored are successively specified by a using a counter 6 inputting clocks from a clock signal generating circuit 5 to output number information and the number information is stored in a memory built in a computer 9 through an analog switch 8. At the time of requesting an ID number, a request signal is sent to the computer 9 through an I/O bus 1 and a gate 11 and whether the request is proper or not is checked on the basis of an ID number checking program. When the request is proper, the request is outputted to the bus 1 as serial data through a gate 12 to execute the program.