5 while and wend – ARM VERSION 1.2 User Manual

Page 314

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Directives Reference

7-32

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

ARM DUI 0068B

7.4.5

WHILE and WEND

The

WHILE

directive starts a sequence of instructions or directives that are to be

assembled repeatedly. The sequence is terminated with a

WEND

directive.

Syntax

WHILE logical-expression

code

WEND

where:

logical-expression

is an expression that can evaluate to either

{TRUE}

or

{FALSE}

(see Logical

expressions on page 3-23).

Usage

Use the

WHILE

directive, together with the

WEND

directive, to assemble a sequence of

instructions a number of times. The number of repetitions can be zero.

You can use

IF...ENDIF

conditions within

WHILE...WEND

loops.

WHILE...WEND

loops can be nested (see Nesting directives on page 7-26).

Example

count SETA 1 ; you are not restricted to
WHILE count <= 4 ; such simple conditions
count SETA count+1 ; In this case,
; code ; this code will be
; code ; repeated four times
WEND

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