| 摘要 |
PROBLEM TO BE SOLVED: To perform safe writing control so that the limit of frequency is not exceeded when data are written to a nonvolatile RAM whose writing frequency is limited. SOLUTION: When the frequency of image formation of an image forming device is counted and the count value is written to the nonvolatile RAM, the limit of frequency is set to 1,000,000 and the guaranteed total frequency of image formation is set to 2,000,000. Two areas A and B are set as storage areas and both are initialized to 0. When the count value of a counter increases, a count value 1 is written to the area A and when the count value increases next time, a count value 2 is written to the area B. Then when a count value 3 is written, the count value 3 is written to the area A having the smaller value since 1 is put in the area A and 2 is put in the area B. Similarly, count values are written to B, A, B, A... in order. To know the total count value at a certain point of time, a larger value between the count values in the areas A and B is considered to be the total count value. |
