Omron CJ1W-CT021 Operation Manuals page 88

3 Operation and Configuration
Additional Information
• The CPU exchanges data with the Simple Counter via the device variables for CJ-series Unit
(for input/output).
• If a Counter is set as a Simple Counter, it is indicated in the device variables for CJ-series Unit
(for input).
• The device variables for CJ-series Unit (for setting) that set Counter functions are not used for
a Simple Counter.
Controlling Simple Counters via Device Variables for CJ-series Unit (for
input/output)
You can control Simple Counters from device variables for CJ-series Unit (for input/output). For
details on device variables for CJ-series Unit (for input/output), refer to 4-2-3 Details of Device Vari-
ables for CJ-series Unit (for input/output).
The following gives a detailed description of all the features and functions for Simple Counters that
are available in device variables for CJ-series Unit (for input/output).
32 Bits Counting Range
A Simple Counter has the full counting range (=32 bits) available to count up- or downwards over
the positive and negative counting range between the Lower Count Limit (–2,147,483,648) and the
Upper Count Limit (+2,147,483,647).
Lower Count Limit
-2,147,483,648
(=80000000
Underflow
Overflow and Underflow
If a Counter Value exceeds the upper or lower limit, it is reflected to the following device variables
for CJ-series Unit (for input) as an overflow or underflow. The Counter Value is retained as the time
of overflow or underflow, and subsequent pulses are ignored. You can clear overflow and underflow
with a preset or reset.
Name of device variable
for CJ-series Unit
*_Ch1_CtOvf
*_Ch2_CtOvf
*_Ch1_CtUdf
*_Ch2_CtUdf
3-8
0
)
H
Up Counting
Counter Value
Type Name
BOOL Counter Overflow
BOOL Counter Underflow
CJ-series High-speed Counter Units Operation Manual for NJ-series CPU Unit(W492)
Upper Count Limit
+2,147,483,647
(=7FFFFFFF
Down Counting
Overflow
1: Overflow
0: Other than the above
1: Underflow
0: Other than the above
)
H
Function