| 摘要 |
PURPOSE:To monitor the rewriting of the contents of a storage element by comparing the contents of the storage element with a check sum of the element in an interruption processing routine generated in each rewriting of information in the storage element. CONSTITUTION:A specific area of the storage element 102 is used as a check sum area, and when data are written in the element 102, a CPU 101 is interrupted. In the case of writing data in the element 102, a new check sum for the element 102 is calculated in each writing of data, the calculated value is written in the check sum area and the check sum of the element 102 is calculated also by an interruption processing program corresponding to an interruption generated in each data writing and compared with the value of the check sum area. When both the values are different as the result of comparison, the whole storage element 102 is rewritten to a system default value by the interruption processing program and the system is reset, or a message is informed to a user. |
