If the access is word aligned then it could be performed using a burst of length 1 and size 32-bit, all the strobes within this container will be asserted. If the access is not word aligned, but does not cross a 64-bit boundary then it could be performed using a burst of 1 length and size 64-bit, this access will only have 4 out of the possible 8 strobes asserted. If the access is across a 64-bit boundary then it could be performed using a burst of length 2 with size 32.

This is just a recommendation on how the access should be performed, but it is not the only legal way in which the transaction can occur. For example, it would be correct protocol to perform a 32-bit burst of length 2 in all cases and just assert the strobes as required, which in some cases would mean that all the strobes are de-asserted for one of the two data transfers.

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