5 dcb – ARM VERSION 1.2 User Manual

Page 300

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Directives Reference

7-18

Copyright © 2000, 2001 ARM Limited. All rights reserved.

ARM DUI 0068B

7.3.5

DCB

The

DCB

directive allocates one or more bytes of memory, and defines the initial runtime

contents of the memory.

=

is a synonym for

DCB

.

Syntax

{label} DCB expr{,expr}...

where:

expr

is either:

A numeric expression that evaluates to an integer in the range –128
to 255 (see Numeric expressions on page 3-20).

A quoted string. The characters of the string are loaded into
consecutive bytes of store.

Usage

If

DCB

is followed by an instruction, use an

ALIGN

directive to ensure that the instruction

is aligned. See ALIGN on page 7-50 for more information.

See also:

DCD and DCDU on page 7-19

DCQ and DCQU on page 7-24

DCW and DCWU on page 7-25

SPACE on page 7-17.

Example

Unlike C strings, ARM assembler strings are not null-terminated. You can construct a
null-terminated C string using

DCB

as follows:

C_string DCB "C_string",0

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