SAM4L Datasheet, PDF (898/1185 Pages) ATMEL Corporation – ATSAM ARM-based Flash MCU

Figure 33-2. Internal Trigger
ATSAM4L4/L2
Figure 33-3. External Trigger
33.6.4
Write Protection Registers
In order to provide security to the DACC, a write protection mode is implemented. This mode is
enabled by writing a one in Write Protect Enable (WPE) in the Write Protect Mode Register
(WPMR) and disabled by writing a zero. Writing to WPMR requires to write a security key in
Write Protect Key (WPMR.WPKEY). The value is “DAC” in ASCII, corresponding to 0x444143.
The write protection mode prevents the write of Mode Register. When this mode is enabled and
the protected registers is written, an error is generated in the Write Protect Status Register
(WPSR) and the register write request is canceled. When a write protection error occurs, the
Write Protection Error bit (WPROTERR) is set to one.
42023C–SAM–02/2013
898