Datasheet

43
11011B–ATARM–21-Feb-12
SAM3N
In Thread mode, the CONTROL register controls whether the processor uses the main stack or
the process stack, see “CONTROL register” on page 52. In Handler mode, the processor always
uses the main stack. The options for processor operations are:
10.4.3 Core registers
The processor core registers are:
Table 10-1. Summary of processor mode, execution privilege level, and stack use options
Processor
mode
Used to
execute
Privilege level for
software execution Stack used
Thread Applications
Privileged or
unprivileged
(1)
1. See “CONTROL register” on page 52.
Main stack or process
stack
(1)
Handler
Exception
handlers
Always privileged Main stack
SP (R13)
LR (R14)
PC (R15)
R5
R6
R7
R0
R1
R3
R4
R2
R10
R11
R12
R8
R9
Low registers
High registers
MSP
‡
PSP
‡
PSR
PRIMASK
FAULTMASK
BASEPRI
CONTROL
General-purpose registers
Stack Pointer
Link Register
Program Counter
Program status register
Exception mask registers
CONTROL register
Special registers
‡
Banked version of SP