Atmel SAM4S Xplained Pro Starter and Evaluation Kit ATSAM4S-XPRO ATSAM4S-XPRO Data Sheet
Product codes
ATSAM4S-XPRO
247
SAM4S Series [DATASHEET]
Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14
12.11.2.2MPU Control Register
Name:
MPU_CTRL
Access:
Read
/Write
Reset:
0x00
000800
The MPU CTRL register enables the MPU, enables the default memory map background region, and enables the use of
the MPU when in the hard fault, Non-maskable Interrupt (NMI), and FAULTMASK escalated handlers.
• PRIVDEFENA: Privileged Default Memory Map Enable
Enables privileged software access to the default memory map:
0: If the MPU is enabled, disables the use of the default memory map. Any memory access to a location not covered by
0: If the MPU is enabled, disables the use of the default memory map. Any memory access to a location not covered by
any enabled region causes a fault.
1: If the MPU is enabled, enables the use of the default memory map as a background region for privileged software
1: If the MPU is enabled, enables the use of the default memory map as a background region for privileged software
accesses.
When enabled, the background region acts as a region number -1. Any region that is defined and enabled has priority over
When enabled, the background region acts as a region number -1. Any region that is defined and enabled has priority over
this default map.
If the MPU is disabled, the processor ignores this bit.
If the MPU is disabled, the processor ignores this bit.
• HFNMIENA: Hard Fault and NMI Enable
Enables the operation of MPU during hard fault, NMI, and FAULTMASK handlers.
When the MPU is enabled:
0: MPU is disabled during hard fault, NMI, and FAULTMASK handlers, regardless of the value of the ENABLE bit.
1: The MPU is enabled during hard fault, NMI, and FAULTMASK handlers.
When the MPU is disabled, if this bit is set to 1, the behavior is unpredictable.
When the MPU is enabled:
0: MPU is disabled during hard fault, NMI, and FAULTMASK handlers, regardless of the value of the ENABLE bit.
1: The MPU is enabled during hard fault, NMI, and FAULTMASK handlers.
When the MPU is disabled, if this bit is set to 1, the behavior is unpredictable.
• ENABLE: MPU Enable
Enables the MPU:
0: MPU disabled.
1: MPU enabled.
0: MPU disabled.
1: MPU enabled.
31
30
29
28
27
26
25
24
–
23
22
21
20
19
18
17
16
–
15
14
13
12
11
10
9
8
–
7
6
5
4
3
2
1
0
–
PRIVDEFENA
HFNMIENA
ENABLE