Dmb - ST STM32F4 Series Programming Manual

The STM32 Cortex-M4 instruction set
3.11.3

DMB

Data memory barrier.
Syntax
DMB{cond}
Where: 'cond' is an optional condition code, see
Operation
DMB acts as a data memory barrier. It ensures that all explicit memory accesses that
appear, in program order, before the DMB instruction are completed before any explicit
memory accesses that appear, in program order, after the DMB instruction. DMB does not
affect the ordering or execution of instructions that do not access memory.
Condition flags
This instruction does not change the flags.
Examples
DMB
182/260
; Data Memory Barrier
DocID022708 Rev 6
Conditional execution on page
PM0214
64.