218 Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Chapter 4 Input/Output Instructions (MSG, GSV, SSV, IOT)
Example 1: When the IOT instruction executes, it immediately sends the values of the
Local:5:0 tag to the output module.
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IOT (Local:5:O);
Example 2: This controller controls station 24 and produces data for the next station (station
25). To use an IOT instruction to signal the transmission of new data, the
produced tag is configured as shown below:
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Produced_Tag is configured to update its event trigger via an IOT
instruction.
If New_Data = on, then the following occurs for one scan:
The CPS instruction sets Produced_Tag = Source_Tag.
The IOT instruction updates Produced_Tag and sends this update to the consuming controller (station 25). When the consuming
controller receives this update, it triggers the associated event task in that controller.
IF New_Data AND NOT Trigger_Consumer THEN
CPS (Source_Tag,Produced_Tag,1);
IOT (Produced_Tag);
END_IF;
Trigger_Consumer := New_Data;