Datasheet

SAM4E [DATASHEET]
Atmel-11157D-ATARM-SAM4E16-SAM4E8-Datasheet_12-Jun-14
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12.6.12.4 DSB
Data Synchronization Barrier.
Syntax
DSB{cond}
where:
cond is an optional condition code, see “Conditional Execution” .
Operation
DSB acts as a special data synchronization memory barrier. Instructions that come after the DSB, in program
order, do not execute until the DSB instruction completes. The DSB instruction completes when all explicit memory
accesses before it complete.
Condition Flags
This instruction does not change the flags.
Examples
DSB ; Data Synchronization Barrier
12.6.12.5 ISB
Instruction Synchronization Barrier.
Syntax
ISB{cond}
where:
cond is an optional condition code, see “Conditional Execution” .
Operation
ISB acts as an instruction synchronization barrier. It flushes the pipeline of the processor, so that all instructions
following the ISB are fetched from cache or memory again, after the ISB instruction has been completed.
Condition Flags
This instruction does not change the flags.
Examples
ISB ; Instruction Synchronization Barrier