20.4.3.2 Erasing the Code Section

The algorithm for erasing all pages of the Flash code section is as follows:
  1. Write the 0x14 (SECTION_ERASE) to the NVMCMD register
  2. Start the erase operation by writing a dummy byte to the high byte of any word location inside the code section
  3. Wait until the NVMBSY bit has been cleared