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

SAM4S Series [DATASHEET]

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

194

Wait For Event.
Syntax

WFE{cond}

where:
condis an optional condition code, see 

.

Operation
WFE is a hint instruction.
If the event register is 0, WFE suspends execution until one of the following events occurs:



An exception, unless masked by the exception mask registers or the current priority level



An exception enters the Pending state, if SEVONPEND in the System Control Register is set



A Debug Entry request, if Debug is enabled



An event signaled by a peripheral or another processor in a multiprocessor system using the SEV 

instruction.

If the event register is 1, WFE clears it to 0 and returns immediately.
For more information, see 

.

Condition Flags
This instruction does not change the flags.
Examples

WFE

; Wait for event 

Wait for Interrupt.
Syntax

WFI{cond}

where:
condis an optional condition code, see 

.

Operation
WFI is a hint instruction that suspends execution until one of the following events occurs:



An exception



A Debug Entry request, regardless of whether Debug is enabled.

Condition Flags
This instruction does not change the flags.
Examples

WFI ; Wait for interrupt