MC68HC12 Datasheet, PDF (122/478 Pages) Motorola, Inc – The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit

Flash Memory
8.11 Flash protection bit FPOPEN
The FPOPEN bit is located in EEMCR – EEPROM Module Configuration
Register, bit 4.
FPOPEN – Opens the Flash array for program or erase
0 = The whole Flash array is protected.
1 = The whole Flash array is enabled for program or erase
FPOPEN can be read at anytime.
FPOPEN can be written only to ’0’ for protection but not to ’1’ for un-
protect in normal mode.
FPOPEN can be written ’0’ and ’1’ in special mode only.
FPOPEN is loaded at reset from EEPROM SHADOW word bit 4.
When FPOPEN is cleared to ’0’, the Flash array cannot be
reprogrammed in normal modes.
CAUTION:
Programming the NVM FPOPEN bit in the SHADOW word ($_FC0, bit
4) means that the FPOPEN bit in the EEMCR register will always be ’0’
in normal modes. The flash array can no longer be modified in normal
modes.
Technical Data
122
Flash Memory
MC68HC912DT128A — Rev 4.0
MOTOROLA