Texas Instruments TMS320C2XX User Manual

Page 166

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How To Use the Instruction Descriptions

7-13

Assembly Language Instructions

[, x]

Operand x is optional.
Example:

For the syntax:
ADD

dma, [, shift]

you must supply

dma, as in the instruction:

ADD 7h

and you have the option of adding a

shift value,

as in the instruction:

ADD 7h, 5

[, x1 [, x2]]

Operands x1 and x2 are optional, but you cannot include x2
without also including x1.
Example:

For the syntax:
ADD

ind, [, shift [, ARn]]

you must supply

ind, as in the instruction:

ADD *+

You have the option of including

shift,

as in the instruction:

ADD *+, 5

If you wish to include AR

n, you must also

include

shift, as in:

ADD *+, 0, AR2

#

The # symbol is a prefix for constants used in immediate
addressing. For short- or long- immediate operands, it is
used in instructions where there is ambiguity with other
addressing modes.
Example:

RPT #15

uses short immediate addressing. It

causes the next instruction to be repeated 16
times. But

RPT 15

uses direct addressing.

The number of times the next instruction
repeats is determined by a value stored in
memory.

Finally, consider this code example:

MoveData

BLDD

DAT5, #310h

;move data at address
;referenced by DAT5 to address
;310h.

Note the optional label

MoveData

used as a reference in front of the instruc-

tion mnemonic. Place labels either before the instruction mnemonic on the
same line or on the preceding line in the first column. (Be sure there are no
spaces in your labels.) An optional comment field can conclude the syntax ex-
pression. At least one space is required between fields (label, mnemonic, op-
erand, and comment).

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