| 摘要 |
<p>PROBLEM TO BE SOLVED: To make a memory control device limitlessly rewritable, by setting an area for storing a use state to EEPROMS of being used and spare systems permitting a finite count of rewritings, switching to the spare system when the use state is against regulations, and displaying the fact. SOLUTION: A flag/pointer area for writing an address of a block being used and a count filed for storing a count of reloadings are set on an EEPROM 1 of a system used at present. Only one block is used at al times, and a next block is used when the count of reloadings to the block reaches a regulated value. When all blocks of the EEPROM 1 of the current system are used up, a swithcing control circuit 3 sets a fresh block to an EEPROM 2 of a spare system and switches a spare system used heretofore to be a fresh current system after data of a final block of the current system are transferred. A computer 7 controls the total operation by a memory control means 6 of software and informs a user of use states of the EEPROMs 1, 2 through a display 5.</p> |
