Up/down count function – Rockwell Automation 1756-LSC8XIB8I ControlLogix Low-speed Counter Module User Manual

Page 16

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Rockwell Automation Publication 1756-UM536A-EN-P - April 2012

Chapter 2

Module Operation

Up/Down Count Function

The Up/Down Count function causes a counter to increment or decrement
accumulated count or changes the direction bit for frequency values.

To invoke the Up/Down Count function for a counter by using the hardware
input method, tie the function to a hardware input on the Input Configuration
tab of the Module Properties dialog box as shown in

Figure 3

.

Figure 3 - Up/Down Count Function Controlled by Hardware Input

When tied to a hardware input, this function is level-sensitive resulting in a
change of status when the input is either low or high:

By default, the count direction goes up when the input is low and down

when the input is high.

When the function is inverted, the count direction goes up when an input

is high and down when the input is low.

Up/Down Count function for counter 1

is tied to hardware input 3.

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