Datasheet

SAM3X / SAM3A [DATASHEET]
Atmel-11057C-ATARM-SAM3X-SAM3A-Datasheet_23-Mar-15
302
18.4.3.8 Unique Identifier
Each part is programmed with a 128-bit Unique Identifier. It can be used to generate keys for example.
To read the Unique Identifier the sequence is:
 Send the Start Read unique Identifier command (STUI) by writing the Flash Command Register with the
STUI command.
 When the Unique Identifier is ready to be read, the FRDY bit in the Flash Programming Status Register
(EEFC_FSR) falls.
 The Unique Identifier is located in the first 128 bits of the Flash memory mapping. So, at the address
0x80000-0xFFFFF.
 To stop the Unique Identifier mode, the user needs to send the Stop Read unique Identifier command (SPUI)
by writing the Flash Command Register with the SPUI command.
 When the Stop read Unique Identifier command (SPUI) has been performed, the FRDY bit in the Flash
Programming Status Register (EEFC_FSR) rises. If an interrupt was enabled by setting the FRDY bit in
EEFC_FMR, the interrupt line of the NVIC is activated.
Note that during the sequence, the software can not run out of Flash (or the second plane in case of dual plane).