Instruction Manual

280 Language Reference • Reference

Publication 1398-PM601A-EN-P — October 2000

WORDS

WHILE

While Program Structure

Purpose The WHILE condition statement executes the statement(s) repeatedly while the condi-

tion specified is TRUE.

Syntax WHILE condition statement(s)

condition The condition to be tested. The condition may be a comparison,

an input being ON or OFF, or a flag being ON or OFF.

Comparisons compare the values of two operands and determine

if the condition is TRUE or FALSE. A comparison may be

greater than (>), less than (<), equal to ( = ), not equal to (<>),

less than or equal to (< = ), or greater than or equal to (> = ). The

operands of a comparison may be user variables, system vari-

ables, analog input values (ADC), or constants.

I1 ON ;an input

F1 ON ;a user flag

INPOSN ;system flag

G1 > G2 ;comparison user variable

G1 > POS1 ;comparison system variable

POS2 <= 7.00 ;comparison constant

statement(s) Any valid language statement. Multiple statements can enclosed

in curly braces {}.

Remarks Unlike the Do While statement, the condition is tested before any statement in the loop

is executed. If the condition is FALSE when the loop begins, the loop body is never

executed.