Before a page can be written, the row containing that page must be erased. The Erase Row command can be used to erase the desired row in the NVM (same command for FLASH, Data FLASH and NVM Rows). Erasing the row sets all bits to '1'. If the row resides in a region that is locked, the erase will not be performed and the Lock Error bit in the INTFLAG register (INTFLAG.LOCKE) will be set.