Cortex-M0+ Devices Generic User Guide
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3.7.12. WFI

Wait for Interrupt.

Syntax

WFI

Operation

WFI suspends execution until one of the following events occurs:

  • an exception

  • an interrupt becomes pending that would preempt if PRIMASK.PM was clear

  • a Debug Entry request, regardless of whether debug is enabled.

Note

WFI is intended for power saving only. When writing software assume that WFI might behave as a NOP operation.

Restrictions

There are no restrictions.

Condition flags

This instruction does not change the flags.

Examples

    WFI ; Wait for interrupt
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