Galil DMC-1800, DMC-1700 user manual Using the ELSE Command, Nesting IF Conditional Statements

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-1700/1800 allows for IF conditional statements to be included within other IF conditional statements. This technique is known as ‘nesting’ and the DMC-1700/1800 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.

Example using IF, ELSE and ENDIF:

#TEST	Begin Main Program “TEST”
II,,3	Enable input interrupts on input 1 and input 2
MG “WAITING FOR INPUT 1, INPUT 2”	Output message
#LOOP	Label to be used for endless loop
JP #LOOP	Endless loop
EN	End of main program
#ININT	Input Interrupt Subroutine
IF (@IN[1]=0)	IF conditional statement based on input 1
IF (@IN[2]=0)	2nd IF conditional statement executed if 1st IF conditional true
MG “INPUT 1 AND INPUT 2 ARE ACTIVE”	Message to be executed if 2nd IF conditional is true
ELSE	ELSE command for 2nd IF conditional statement
MG “ONLY INPUT 1 IS ACTIVE	Message to be executed if 2nd IF conditional is false
ENDIF	End of 2nd conditional statement
ELSE	ELSE command for 1st IF conditional statement
MG”ONLY INPUT 2 IS ACTIVE”	Message to be executed if 1st IF conditional statement
ENDIF	End of 1st conditional statement
#WAIT	Label to be used for a loop
JP#WAIT,(@IN[1]=0) (@IN[2]=0)	Loop until both input 1 and input 2 are not active
RI0	End Input Interrupt Routine without restoring trippoints

148 • Chapter 7 Application Programming DMC-1700/1800