STORED DATA INSPECTION OF DIGITAL MEMORY MEANS

PROBLEM TO BE SOLVED: To reduce changes, as much as possible, required for check with a check program when the stored data is changed by changing a check sum adjustment data so that the total sum adding all stored data including the check sum adjustment data written together with the write data. SOLUTION: In the case of checking an error of stored data of EPROM3 with a check program of a personal computer 9 by storing a check sum adjustment data to a digital storing means EPROM storing the control program, checking is made by determining whether the total sum of the stored data of EPROM3 including the check sum adjustment data becomes a constant value or not. When the control program is corrected, the check sum adjustment data is changed to make constant the total sum. Thereby, even if the control program is corrected, it is not required to change the check program of the personal computer 9 and thereby check can be conducted easily.