| 摘要 |
<p>PURPOSE:To substantially increase the number of writing of an EEPROM and use without considering a writing limit number of the EEPROM by using a preliminary data information area and performing a writing when a condition of an address is checked at every time of data information writing and an abnormality is discriminated. CONSTITUTION:In an EEPROM 1, a memory area is constituted of an area A in which address information of a data is stored, an area B in which data information is stored, and an area C storing a newest address of a preliminary data information area B' which is not used for storing the information in the data information area B. Between a central arithmetic processing unit CPU 2, an EPROM 3 in which address information, a program or the like are stored, and a random access memory RAM 4 in which a contemporary data is stored which may be lost when a power source is broken, an exchange of the data information and the address information is performed through a bus 5.</p> |
