| 摘要 |
PURPOSE:To easily discover a correct value by analyzing the data deformation of data to be changed on fixed rules by successively changing three data at the time of storing new data in first, second and third storage areas in this order and reading these data each time these data are generated. CONSTITUTION:An operating mechanism part 11 and a memory 12 are connected to a CPU 10 of a copy machine, Areas A, B and C to accumulate the number of copied data are set to the memory 12. The same data are stored in these areas in the order of A, B and C. The CPU reads count data, first of all, reads the contents of the A and B registers and judges whether A=B is established or not. In the case of Anot equal to B, the contents of the C register are also read out and the B and C are compared. In the case of B=C, it is judged that operational abnormality is generated at the write time of A. In the case of Anot equal to Bnot equal to C, it is judged that operational abnormality is generated in the case of storing B although A is correctly stored. |
