Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD Data Sheet

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SAM4S Series [DATASHEET]

Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14

EXC_RETURN is the value loaded into the LR on exception entry. The exception mechanism relies on this value 

to detect when the processor has completed an exception handler. The lowest five bits of this value provide 

information on the return stack and processor mode. 

 shows the EXC_RETURN values with a 

description of the exception return behavior. 
All EXC_RETURN values have bits[31:5] set to one. When this value is loaded into the PC, it indicates to the 

processor that the exception is complete, and the processor initiates the appropriate exception return sequence. 

0xFFFFFFF1

Return to Handler mode, exception return uses non-floating-point state 

from the MSP and execution uses MSP after return.

0xFFFFFFF9

Return to Thread mode, exception return uses non-floating-point state from 

MSP and execution uses MSP after return.

0xFFFFFFFD

Return to Thread mode, exception return uses non-floating-point state from 

the PSP and execution uses PSP after return.