| 摘要 |
<p>PROBLEM TO BE SOLVED: To shorten the data writing time by storing a data temporarily in a FIFO memory at the time of writing, selecting an updating data and storing the updating data in FIFO memory thereby enabling flush erasure of the updating data. SOLUTION: At the time of writing a data, a comparing circuit 4 compares a specific word data at a nonvolatile memory section 6 with a data written from a data I/O butter 1 and delivers a detection signal only when they do not match each other. Consequently, a previously inputted write data D0-D7 and address data An-A0 are stored in the FIFO memory 5 and the write operation is disabled when the write data matches the data in nonvolatile memory section 6 at a corresponding address. The operation is continued and the data in nonvolatile memory section 6, the mismatching write data and the address data thereof are stored continuously in the FIFO memory 5. When the data is stored over the entire area, a control circuit 7 notifies that the data is updated to the outside.</p> |
