Using the IF and ENDIF Commands
An IF conditional statement is formed by the combination of an IF and ENDIF command. The IF
command has as its arguments one or more conditional statements. If the conditional statement(s)
evaluates true, the command interpreter will continue executing commands which follow the IF
command. If the conditional statement evaluates false, the controller will ignore commands until
the associated ENDIF command is executed OR an ELSE command occurs in the program (see
discussion of ELSE command below).
Note:
An ENDIF command must always be executed for every IF command that has been
executed. It is recommended that the user not include jump commands inside IF conditional
statements since this causes re-direction of command execution. In this case, the command
interpreter may not execute an ENDIF command.
Using the ELSE Command
The ELSE command is an optional part of an IF conditional statement and allows for the
execution of command only when the argument of the IF command evaluates False. The ELSE
command must occur after an IF command and has no arguments. If the argument of the IF
command evaluates false, the controller will skip commands until the ELSE command. If the
argument for the IF command evaluates true, the controller will execute the commands between
the IF and ELSE command.
Nesting IF Conditional Statements
The DMC-1600 allows for IF conditional statements to be included within other IF conditional
statements. This technique is known as 'nesting' and the DMC-1600 allows up to 255 IF
conditional statements to be nested. This is a very powerful technique allowing the user to specify
a variety of different cases for branching.
Command Format - IF, ELSE and ENDIF
FORMAT: DESCRIPTION
IF conditional statement(s)
Execute commands proceeding IF command (up to ELSE command) if
conditional statement(s) is true, otherwise continue executing at ENDIF
command or optional ELSE command.
ELSE
Optional command. Allows for commands to be executed when argument
of IF command evaluates not true. Can only be used with IF command.
ENDIF
Command to end IF conditional statement. Program must have an ENDIF
command for every IF command.
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Chapter 7 Application Programming
DMC-1600
