5.8.28. DCWU directive

The DCWU directive allocates one or more unaligned halfwords of memory, and defines the initial runtime contents of the memory.

Syntax

The syntax of DCWU is:

{label} DCWU expression{,expression}...

where:

expression

is a numeric expression that evaluates to an integer in the range –32768 to 65535. See Numeric expressions.

Usage

Use DCWU to define data halfwords with arbitrary alignment, in packed structures for example.

You must use a DATA directive if you use DCWU to define labeled data within Thumb code. Refer to DATA directive for more information.

If DCWU is followed by code, use an ALIGN directive to ensure that instructions are word aligned. Refer to ALIGN directive for more information.

DCWU does not insert padding when preceding code is unaligned. Use DCW if you require alignment.

See also:

Example

		AREA		DataB2, DATA, READWRITE
oddbits		DCB		1,2,3				; now not word aligned
		DCWU		number,-255,4				; these will each occupy two
								; bytes, but not necessarily
								; aligned
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