| 摘要 |
PURPOSE:To detect an abnormality to recognize a data in such a case where only S00 and SFF are written in a RAM by providing a recognizing RAM correspondingly to plural data RAM in a standby RAM holding after a power source is broken. CONSTITUTION:For instance, as a RAM of a data, six RAMs 1-6 and as a RAM for recognizing, a RAM 7 are provided. If the data of the RAMs 1-6 are considered to be S46, S52, S65, S60, S30, and S06, a sum of the data RAMs is S193. This sum is represented by a subordinate 1 byte and a total sum including the RAM 7 is represented, similarly by the subordinate 1 byte. If respectively, S93, S56 are obtained, a value X to be set in the RAM 7 is expressed by X=S56-S93=SC3. In order to recognize the data of the RAM, obtaining a total sum of the value of the RAM 1-6 and the value of the RAM 7, S193+SC3=S256 is obtained if there is no abnormality in the data. If the subordinate 1 byte s taken, S56 is obtained, coinciding with a predetermined total sum value S56 and the recognition that the data is normal is made. |
