SAM3U_14 Datasheet, PDF (317/1187 Pages) ATMEL Corporation – From 64 to 256 Kbytes embedded Flash

SAM3U Series
21.4.3.7
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, thus, at the
address 0x80000-0x8000F.
• 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).
21.5 Enhanced Embedded Flash Controller (EEFC) User Interface
The User Interface of the Enhanced Embedded Flash Controller (EEFC) is integrated within the System Controller with
base address 0x400E0800.
Table 21-3.
Offset
0x00
0x04
0x08
0x0C
0x10
Register Mapping
Register
EEFC Flash Mode Register
EEFC Flash Command Register
EEFC Flash Status Register
EEFC Flash Result Register
Reserved
Name
EEFC_FMR
EEFC_FCR
EEFC_FSR
EEFC_FRR
–
Access
Read-write
Write-only
Read-only
Read-only
–
Reset State
0x0
–
0x00000001
0x0
–
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