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The processor supports the following data types:
doubleword, 64-bit
word, 32-bit
halfword, 16-bit
byte, 8-bit.
when any of these types are described as unsigned, the N-bit data value represents a non-negative integer in the range 0 to +2N-1, using normal binary format
when any of these types are described as signed, the N-bit data value represents an integer in the range -2N-1 to +2N-1-1, using two’s complement format.
For best performance you must align these as follows:
word quantities must align with 4-byte boundaries
halfword quantities must align with 2-byte boundaries
byte quantities can be placed on any byte boundary.
The processor provides mixed-endian and unaligned access support. See Chapter 4 Unaligned Data and Mixed-endian Data Support for details.
You cannot use LDRD, LDM, LDC, STRD, STM,
or STC instructions to access 32-bit quantities if they
are unaligned.
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