PURPOSE: To improve the reliability of data by exactly writing and reading data in an E2PROM.
CONSTITUTION: The writing data are written in the first prescribed address of an E2PROM 100 and afterwards, the data are immediately read out. When the written data and the read data are not matched, an address different from the conventional address is designated, and write and read operations are repeated until the both data are matched. When the both data are matched, the write is completed and the address writing the match data is written in the second prescribed address of the E2PROM 100, which is not overlapped in the address area of the written data, as data. In the case of reading, the address writing the match data is read out of the second prescribed address and with the read address, the written data are read out of the E2PROM 100.
SHIINA MICHIHIRO
IWAI FUMIO
