Omron SYSMAC CJ - REFERENCE MANUAL 01-2008 Reference Manual page 1237

Block Programming Instructions
Description
1198
Operation without an Operand for IF(802)
If an operand bit is not specified, an execution must be created before IF(802)
starting with LD. If the execution condition is ON, the instructions between
IF(802) and ELSE(803) will be executed and if the execution condition is OFF,
the instructions between ELSE(803) and IEND(804) will be executed.
Execution
condition
If the ELSE(803) instruction is omitted and the execution condition is ON, the
instructions between IF(802) and IEND(804) will be executed and if the execu-
tion condition is OFF, only the instructions after IEND(804) will be executed.
Execution
condition
Operation with an Operand for IF(802) or IF NOT(802)
An operand bit, B, can be specified for IF(802) or IF NOT(802). If the operand
bit is ON, the instructions between IF(802) and ELSE(803) will be executed. If
the operand bit is OFF, the instructions between ELSE(803) and IEND(804)
will be executed. For IF NOT(802), the instructions between IF(802) and
ELSE(803) will be executed and if the operand bit is ON, the instructions be
ELSE(803) and IEND(804) will be executed is the operand bit is OFF.
If the ELSE(803) instruction is omitted and the operand bit is ON, the instruc-
tions between IF(802) and IEND(804) will be executed and if the operand bit
is OFF, only the instructions after IEND(804) will be executed. The same will
happen for the opposite status of the operand bit if IF NOT(802) is used.
Execution
condition ON?
"B" executed
"A" executed (be-
tween IF and ELSE).
(after ELSE).
Execution
condition ON?
"A" executed (be-
tween IF and IEND).
Operand bit
ON?
"A" executed (be- "B" executed
tween IF and ELSE).
(after ELSE).
Section 3-32