3.12.13. WFE

Wait For Event.

Syntax

WFE{cond}

Where:

cond

Is an optional condition code. See Conditional execution.

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 Power management.

Condition flags

This instruction does not change the flags.

Examples

    WFE  ; Wait for event 

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