IAI ssel, Operation Manual

Page: 221 / 497

195
Part 2 Programs
1.13 Structural IF

IF

(Structural IF)
Command, declaration
Extension condition
(LD, A, O, AB, OB)
Input condition
(I/O, flag)
Command,
declaration
Operand 1 Operand 2
Output
(Output, flag)
Optional Optional IF

Variable
number
Data CP
[Function] Compare the content of the variable specified in operand 1 with the value specified in
operand 2, and proceed to the next step if the condition is satisfied.
If the condition is not satisfied, the program will proceed to the step next to the corresponding
ELSE command, if any, or to the step next to the corresponding EDIF command.
If the input condition is not satisfied and the IF

command is not executed, the program will
proceed to the step next to the corresponding EDIF.
A maximum of 15 nests are supported when IS

and DW

are combined.
IF

EQ Operand 1 = Operand 2
NE
Operand 1

Operand 2
GT Operand 1 > Operand 2
GE
Operand 1

Operand 2
LT Operand 1 < Operand 2
LE
Operand 1

Operand 2
[Example 1] 600 IFEQ 1 1 Select an axis.
IFGE 2 0 Select a moving direction.
JFWN 01 5 Move axis 1 forward.
ELSE
JBWN 01 5 Move axis 1 backward.
EDIF
ELSE
IFLT 2 0 Select a moving direction.
JBWN 10 5 Move axis 2 backward.
ELSE
JFWN 10 5 Move axis 2 forward.
EDIF
EDIF
Jog by selecting axis 1/axis 2 by variable 1 and forward/backward (+/–) by
variable 2.
Nothing will happen if flag 600 is OFF, in which case the program will proceed to
the step next to the last EDIF.
(Note) Using a GOTO command to branch out of or into an IF

-EDIF syntax is prohibited.