Atmel SAM4S-EK2 Atmel ATSAM4S-EK2 ATSAM4S-EK2 Data Sheet
Product codes
ATSAM4S-EK2
223
SAM4S [DATASHEET]
11100E–ATARM–24-Jul-13
When the ENABLE bit is set to 1, at least one region of the memory map must be enabled for the system to function unless the
PRIVDEFENA bit is set to 1. If the PRIVDEFENA bit is set to 1 and no regions are enabled, then only privileged software can
operate.
PRIVDEFENA bit is set to 1. If the PRIVDEFENA bit is set to 1 and no regions are enabled, then only privileged software can
operate.
When the ENABLE bit is set to 0, the system uses the default memory map. This has the same memory attributes as if the MPU
is not implemented. The default memory map applies to accesses from both privileged and unprivileged software.
is not implemented. The default memory map applies to accesses from both privileged and unprivileged software.
When the MPU is enabled, accesses to the System Control Space and vector table are always permitted. Other areas are acces-
sible based on regions and whether PRIVDEFENA is set to 1.
sible based on regions and whether PRIVDEFENA is set to 1.
Unless HFNMIENA is set to 1, the MPU is not enabled when the processor is executing the handler for an exception with priority
–1 or –2. These priorities are only possible when handling a hard fault or NMI exception, or when FAULTMASK is enabled. Set-
ting the HFNMIENA bit to 1 enables the MPU when operating with these two priorities.
–1 or –2. These priorities are only possible when handling a hard fault or NMI exception, or when FAULTMASK is enabled. Set-
ting the HFNMIENA bit to 1 enables the MPU when operating with these two priorities.