ARM Cortex-M4 - Wfi

The Cortex-M4 Instruction Set
ARM DUI 0553A Copyright © 2010 ARM. All rights reserved. 3-169
ID121610 Non-Confidential
3.12.12 WFI
Wait for Interrupt.
Syntax
WFI{cond}
where:
cond Is an optional condition code, see Conditional execution on page 3-18.
Operation
WFI is a hint instruction that suspends execution until one of the following events occurs:
• a non-masked interrupt occurs and is taken
• an interrupt masked by PRIMASK becomes pending
• a Debug Entry request.
Condition flags
This instruction does not change the flags.
Examples
WFI ; Wait for interrupt