Texas Instruments TMS320C54x, User Manual

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Directives That Initialize Constants
4-13 Assembler Directives
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.float and .xfloat calculate the single-precision (32-bit) IEEE floating-
point representation of a single floating-point value and store it in two con-
secutive words in the current section. The most significant word is stored
first. The .float directive automatically aligns to the long word boundary,
and .xfloat does not.
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.int, .uint, .half, .uhalf, .short, .ushort, .word, and .uword place one or
more 16-bit values into consecutive words in the current section.
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.double and .ldouble calculate the single-precision (32-bit) IEEE floating-
point representation of one or more floating-point values and store them
in two consecutive words in the current section. The .double directive
automatically aligns to the long word boundary.
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.long, .ulong, and .xlong place 32-bit values into two consecutive words
in the current section. The most significant word is stored first. The .long
directive automatically aligns to a long word boundary, and the .xlong
directive does not.
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.string and .pstring place 8-bit characters from one or more character
strings into the current section. The .string directive is similar to .byte, plac-
ing an 8-bit character in each consecutive word of the current section. The
.pstring also has a width of 8 bits but packs two characters into a word. For
.pstring, the last word in a string is padded with null characters (0) if
necessary.
Note: These Directives in a .struct/.endstruct Sequence
The directives listed above do not initialize memory when they are part of a
.struct/.endstruct sequence; rather, they define a member’s size. For more
information about the .struct/.endstruct directives, see Section 4.9,
Assembly-Time Symbol Directives, on page 4-21.
Figure 4–3 compares the .byte, .int, .long, .xlong, .float, .xfloat, .word, and
.string directives. For this example, assume that the following code has been
assembled: