+---------------------------------------+ | S7-300 CPU Protection | +---------------------------------------+ | +--------------------+--------------------+ | | [ Old Generation (Pre-2004) ] [ Modern MMC-Based (Post-2004) ] | | • Uses FEPROM Cards • Uses Encrypted SIMATIC MMCs • Volatile RAM Battery Backup • Password bound to CPU & Card • Clear via Battery Pull • Requires Hex Cloning or MRES Reset