| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an internal memory data write alteration prevention method for preventing an internal memory in an onboard semiconductor sensor from being written and altered by a signal from the outside. <P>SOLUTION: In the internal memory data write alteration prevention method in an onboard semiconductor sensor, a memory area of a nonvolatile memory capable of repeatedly performing writing is divided into two, and writing is permitted to one of the memory areas only when the memory is unused. According to the data write alteration prevention method, the memory area of an EEPROM for storing information such as failure history and so forth that must be repeatedly stored by the self-diagnosis function of the sensor can be shared, and the write alteration of the data can be also prevented. Thus, the sensor having data storage function with high reliability can be provided inexpensively. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
