BUILT-IN CONTROL UNIT

PROBLEM TO BE SOLVED: To provide a technique capable of reading original data correctly without depending on spacial data restoration means even if the original data written in nonvolatile memory of a built-in control unit becomes defective data by aging deterioration of the nonvolatile memory.SOLUTION: A built-in control unit puts together and encodes plural pieces of data to write in an address on nonvolatile memory, as 1 bit, determines whether the data is written in the nonvolatile memory by each address on the nonvolatile memory, and combines and decodes a plurality of determined results.