8.2.3 Write Protection
Write protection allows the device to be protected from unintended self-writes. Applications, such as bootloader software, can be protected while allowing other regions of the program memory to be modified.
The WRTn Configuration bits determine which
of the program memory blocks are protected:
- Application Block Write Protection: The WRTAPP Configuration bit is used to write-protect the Application Block.
- SAF Write Protection: The WRTSAF Configuration bit is used to write-protect the Storage Area Flash.
- Data EEPROM Write Protection: The WRTD Configuration bit is used to write-protect the Data EEPROM.
- Configuration Registers Write Protection: The WRTC Configuration bit is used to write-protect the Configuration Registers.
- Boot Block Write Protection: The WRTB Configuration bit is used to write-protect the Boot Block.
When enabled, the corresponding memory location is write-protected and further programming is disabled, until a Bulk Erase operation is performed on the Configuration memory region. The Boot Block, Data EEPROM, the SAF, and/or the Application Block can still be programmed and read during program execution through the NVM firmware.