Omron NJ-series User Manual page 261

6 Programming
Connecting Functions and Function Blocks in a Ladder Diagram
 Connection Configurations
You use the following two types of connections for functions or function blocks.
1) Power Flow Input and Output
In a ladder diagram, the line that connects an input variable of a function or function block and the
left bus bar indicates a BOOL input and the line that connects an output variable to the right bus bar
indicates a BOOL output.
Example:
Inputs are connected in the power flow that connects to the left bus bar. Outputs are connected in
the power flow that connects to the right bus bar.
x1
2) Parameter Inputs and Parameter Outputs
In a ladder diagram, parameter inputs and outputs are specified when the input and output variables
of a function or function block are not connected to the left and right bus bars.
x1
As shown below, you can specify either variables or constants for input and output parameters.
Function/function block variables
Input variables
Output variables
In-out variables
 Number of BOOL Variables
At least one BOOL variable each is required for the input and the output (such as EN and ENO) of a
function or function block.
Example:
BOOL variable
6-74
FB
IN1
x2 IN2
FB
IN1
IN2
x2
Input parameters
You can specify variables or con-
stants.
---
You can specify only variables.
MyFB
(BOOL) (BOOL)
IN Q
(INT)
Val_In
OUT1
OUT2 y2
OUT1
OUT2
y2
---
You can specify only variables.
You can specify only variables.
BOOL variable
NJ-series CPU Unit Software User's Manual (W501)
y2
y2
Output parameters