Methods for protecting data on an integrated circuit including a memory are described. One method includes storing nonvolatile protection codes on the integrated circuit. The nonvolatile protection codes have a first value indicating a protected state or a second value indicating an unprotected state for respective sectors in a plurality of sectors of the memory. The method includes storing volatile protection codes on the integrated circuit. The volatile protection codes have a first value indicating a protected state or a second value indicating an unprotected state for respective sectors in the plurality of sectors. The method includes blocking modification in a particular sector using circuitry on the integrated circuit when the volatile protection code for the particular sector has the first value, else allowing modification in the particular sector, and setting the volatile protection codes to values of the nonvolatile protection codes in an initialization procedure.