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SAM4S [DATASHEET]

11100E–ATARM–24-Jul-13

In unprivileged software writes to unallocated or execution state bits in the PSR are ignored. 

Note:

When the user writes to BASEPRI_MAX, the instruction writes to BASEPRI only if either:
Rn is non-zero and the current BASEPRI value is 0
Rn is non-zero and less than the current BASEPRI value.

See 

Restrictions

Rn must not be SP and must not be PC.

Condition Flags

This instruction updates the flags explicitly based on the value in Rn.

Examples

MSR  CONTROL, R1 ; Read R1 value and write it to the CONTROL register 

No Operation.

Syntax

NOP{cond}

where:

cond

Operation

NOP does nothing. NOP is not necessarily a time-consuming NOP. The processor might remove it from the pipeline
before it reaches the execution stage.

Use NOP for padding, for example to place the following instruction on a 64-bit boundary.

Condition Flags

This instruction does not change the flags.

Examples

    NOP  ; No operation 

Send Event.

Syntax

SEV{cond}

where:

cond

Operation

SEV is a hint instruction that causes an event to be signaled to all processors within a multiprocessor system. It also sets
the local event register to 1, see 

.

Condition Flags

This instruction does not change the flags.

Examples

    SEV ; Send Event