Galil Motion Control CDS-3310, User Manual

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Chapter 7 Application Programming CDS-3310
Move the A motor to absolute position 1000 counts and back to zero ten times. Wait 100 msec
between moves.
Instruction Interpretation
#BEGIN Begin Program
count=10 Initialize loop counter
#LOOP Begin loop
PA 1000 Position absolute 1000
BGA Begin move
AMA Wait for motion complete
WT 100 Wait 100 msec
PA 0 Position absolute 0
BGA Begin move
AMA Wait for motion complete
WT 100 Wait 100 msec
count = count -1 Decrement loop counter
JP #LOOP, count >0 Test for 10 times thru loop
EN End Program
IF, ELSE, AND ENDIF
The CDS-3310 provides a structured approach to conditional statements using IF, ELSE and ENDIF
commands.
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 it's 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 CDS-3310 allows for IF conditional statements to be included within other IF conditional
statements. This technique is known as 'nesting' and the CDS-3310 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.