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anon10041
05-12-2012, 08:48 PM
Dear Sir,

Could you please explain aligned and non-aligned memory access.

Thanks & Regards,

Anon10041.

anup
05-12-2012, 09:08 PM
Anon10041,

Aligned access means that the addresses are a multiple of some basic number. Most commonly this number is either the word size (e.g. 32bits) or other higher number depending on the peripheral e.g. 256bits or 128bits. The purpose for alignment is that it is faster for hardware to do memory accesses which are a multiple of the chunk size or its bus-width. Some processor instructions specifically require that the memory address be a multiple of word size in order to complete the operation faster. You can see more on this Wikipedia article: http://en.wikipedia.org/wiki/Data_structure_alignment

Thanks,

Anup