US Patent 7551706 Counter device and counting method

A counter device includes: a rewritable counter having a non-volatile memory which requires sector erasure to once turn all data in a sector into high data, prior to changing low data into high data in respective bits; and a control section updating a counter value of the rewritable count by writing in and reading out the data with respect to the rewritable counter using a complement of 1, and thereby controlling writing in and reading out the data of the rewritable counter.