cancel
Showing results for 
Search instead for 
Did you mean: 

STM32F4 DMA source/dest address alignment requirements

Peeters.Bram
Senior

The RM0090 Reference manual (DocID018909 Rev 10) mentions on p310 that :

When the data width (programmed in the PSIZEor MSIZE bits in the DMA_SxCR register)

is a half-word or a word, respectively, the peripheral or memory address written into the

DMA_SxPAR or DMA_SxM0AR/M1AR registers has to be aligned on a word or half-word

address boundary, respectively

However the AN4031 Application note mentions p9:

A DMA transfer is defined by a source address and a destination address. Both the source

and destination should be in the AHB or APB memory ranges and should be aligned to

transfer size

Anyone any insight into that ? Alignment to the transfer size seems strange ?

1 REPLY 1

Terminology problem only: the AN by "transfer size" means "size of one transfer", i.e. in terms of RM it's "data width".

JW