Rockwell Automation Allen-Bradley 1769-ASCII, User Manual

Page: 52 / 118

52 Rockwell Automation Publication 1769-UM012B-EN-P - January 2014
Chapter 2 Configure the 1769-ASCII Module
Input Channel1
The Input Channel1 does the following tasks:
•
Stores the current value, on first scan, of Rx Transaction ID (channel 1) as
most recent.
•
Monitors the lower 8 bits of Rx Transaction ID (upper 8 bit are Tx)
•
Indicates new data when the Rx Transaction ID changes.
•
Copies the data from the module's Input Tags to a STRING tag
(InData1).
•
Indicates to the MainRoutine that new data has arrived.
•
Saves the value of Rx Transaction ID, so you can detect next change.