Cortex-M3 Processor (Reference Material)
UG0331 User Guide Revision 15.0
93
3.6.10.11.1Syntax
WFE{
cond
}
where:
cond
is an optional condition code, see
3.6.10.11.2Operation
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
3.6.10.12 WFI
Wait for Interrupt.
3.6.10.12.1Syntax
WFI{cond}
where:
cond
is an optional condition code, see
3.6.10.12.2Operation
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.
3.6.10.12.3Condition Flags
This instruction does not change the flags.
Examples
WFI ; Wait for interrupt