User manual

1 Publication CNET-UM001C-EN-P - November 2005
Chapter 5
Produce and Consume Tags
(Interlock Controllers)
Use This Chapter
This chapter describes how to interlock (produce and consume tags)
controllers via a ControlNet network.
Interlocking controllers is a method of sharing scheduled data between
controllers. Methods of communicating with other controllers are listed below:
Terminology
A Logix5000 controller lets you produce (broadcast) and consume (receive)
system-shared tags.
For two controllers to share produced or consumed tags, both controllers
must be attached to the same ControlNet network.
Read this
chapter for:
• 1756-CN2, 1756-CN2R modules
• 1756-CNB, 1756-CNBR modules
• 1769-L32C, 1769-L35CR controllers
• 1784-PCICS, 1784-PKTCS cards
• 1788-CNx cards
For This Information See Page
Terminology 5-1
Set Up the Hardware 5-2
Determine Connections for Produced and Consumed Tags 5-3
Organize Tags for Produced or Consumed Data 5-3
Adjust for Bandwidth Limitations 5-6
Produce a Tag 5-7
Consume a Tag 5-9
Additional Steps for a PLC-5C or ControlNet Scanner Card 5-12
If The Data Then See Chapter
Needs regular, fast delivery at an interval that you specify Produce and consume a tag Produce and Consume Tags
(Interlock Controllers)
Is sent when a specific condition occurs in your application Execute a message (MSG)
instruction
Peer-to-Peer Messaging
Term Definition
produced
tag
A tag that a controller makes available for use by other controllers. Multiple
controllers can simultaneously consume (receive) the data. A produced tag
sends its data to one or more consumed tags (consumers) without using logic.
The produced tag sends its data at the RPI of the fastest consuming tag.
consumed
tag
A tag that receives the data of a produced tag. The data type of the consumed
tag must match the data type (including any array dimensions) of the
produced tag. The RPI of the fastest consumed tag determines the period at
which the produced tag is produced.