B1.4.2 Unaligned accesses

The Cortex®‑M33 processor supports unaligned accesses. They are converted into two or more aligned AHB transactions on the C-AHB or S-AHB master ports on the processor.

Unaligned support is only available for load/store singles (LDR, LDRH, STR, STRH, TBH) to addresses in Normal memory. Load/store double and load/store multiple instructions already support word aligned accesses, but do not permit other unaligned accesses, and generate a fault if this is attempted. Unaligned accesses in Device memory are not permitted and fault. Unaligned accesses that cross memory map boundaries are architecturally UNPREDICTABLE.


If CCR.UNALIGN_TRP for the current Security state is set, any unaligned accesses generate a fault.
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