22.4.3.8 Unique Identifier Area

Each device is programmed with a 128-bit unique identifier area .

See “Flash Memory Areas”.

The sequence to read the unique identifier area is the following:

  1. Execute the ‘Start Read Unique Identifier’ command by writing EEFC_FCR.FCMD with the STUI command. Field EEFC_FCR.FARG is meaningless.
  2. Wait until the bit EEFC_FSR.FRDY falls to read the unique identifier area. The unique identifier field is located in the first 128 bits of the Flash memory mapping. The ‘Start Read Unique Identifier’ command reuses some addresses of the memory plane for code, but the unique identifier area is physically different from the memory plane for code.
  3. To stop reading the unique identifier area, execute the ‘Stop Read Unique Identifier’ command by writing EEFC_FCR.FCMD with the SPUI command. Field EEFC_FCR.FARG is meaningless.
  4. When the SPUI command has been executed, the bit EEFC_FSR.FRDY rises. If an interrupt was enabled by setting the bit EEFC_FMR.FRDY, the interrupt line of the interrupt controller is activated.
Note: During the sequence, the software cannot be fetched from the Flash.