Basics: alignment of an address

Basics Alignment of an address
As you probably know, modern computer's memory has byte organization. This means that every byte has its number (address). To read several consequent bytes we usually must specify the address of the first byte and their numbers. Although an address for separate byte can be arbitrary, several types of processors can read only definite groups of bytes: the first byte's address must have "round" value or to say more correct a multiply of 2ⁿ. For example, when you want to read 4 bytes on such machines, you must set the address value, which can be divided by 4 without remainder. In other words address 1200 for such portion of information is valid, but 1201 - not. Such requirement for address values is called data alignment. MMIX is the machine with alignment. Related topics: memory organization numeration of bytes signed an unsigned information "MMIX basics" page
(C) 2001, Evgeny Eremin. rEd-MMI project documentation