Texas Instruments TMS320C54x, User Manual

Page: 116 / 469

Initialize Bytes
.byte
4-33 Assembler Directives
Syntax
.byte value
1
[, ... , value
n
]
.ubyte value
1
[, ... , value
n
]
.char value
1
[, ... , value
n
]
.uchar value
1
[, ... , value
n
]
Description The .byte, .ubyte, .char, and .uchar directives place one or more bytes into
consecutive words of the current section. Each byte is placed in a word by it-
self; the 8 MSBs are filled with 0s. A
value can be:
-
An expression that the assembler evaluates and treats as an 8-bit signed
or unsigned number
-
A character string enclosed in double quotes. Each character in a string
represents a separate value.
Values are not packed or sign-extended; each byte occupies the 8 least signifi-
cant bits of a full 16-bit word. The assembler truncates values greater than 8
bits. You can use up to 100 value parameters, but the total line length cannot
exceed 200 characters.
If you use a label, it points to the location where the assembler places the first
byte.
Note that when you use these directives in a .struct/.endstruct sequence, they
defines a member’s size; they do not initialize memory. For more information
about .struct/.endstruct, see Section 4.9,
Assembly-Time Symbol Directives,
on page 4-21.
Example In this example, 8-bit values (10, –1, abc, and a) are placed into consecutive
words in memory. The label strx has the value 100h, which is the location of
the first initialized word.
1 0000 .space 100h * 16
2 000100 000a STRX .byte 10, –1, ”abc”, ’a’
000101 00ff
000102 0061
000103 0062
000104 0063
000105 0061