Reading the Flash/EEPROM and writing the page buffer is handled with normal
load/store instructions. Other operations, such as writing and erasing the memory arrays,
are handled by commands in the NVM.
To execute a command in the NVM:
- 1.Confirm that any previous operation
is completed by reading the Busy (EEBUSY and FBUSY) Flags in the NVMCTRL.STATUS
register.
- 2.Write the appropriate key to the
Configuration Change Protection (CPU.CCP) register to unlock the NVM Control A
(NVMCTRL.CTRLA) register.
- 3.Write the desired command value to
the CMD bit field in the Control A (NVMCTRL.CTRLA) register within the next four
instructions.