Publication 1763-RM001C-EN-P - October 2009
I/O Configuration
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3.
Open slot 0 (controller).
4.
Select the “embedded I/O configuration” tab.
5.
Select the mask bits for the inputs that you want to operate as
latching inputs.
6.
Select the state for the latching inputs. The controller can detect
both “on” (rising edge) and “off” (falling edge) pulses, depending
upon the configuration selected in the programming software.
The following information is provided for a controller looking for an “on”
pulse. When an external signal is detected “on”, the controller “latches”
this event. In general, at the next input scan following this event, the
input image point is turned “on” and remains “on” for the next controller
scan. It is then set to “off” at the next input scan. The following figures
help demonstrate this.
Rising Edge Behavior - Example 1
Scan Number (X)
Scan Number (X+1)
Scan Number (X+2)
External
Input
Latched
Status
Input File
Value
Input
Scan
Ladder
Scan
Output
Scan
Input
Scan
Ladder
Scan
Output
Scan
Input
Scan
Ladder
Scan
Output
Scan
efesotomasyon.com - Allen Bradley,Rockwell,plc,servo,drive