User manual

Publication 1768-UM001C-EN-P - November 2007
28 Communicate over Networks
1768-CNB and 1768-CNBR ControlNet Modules
CompactLogix ControlNet communication modules bridge ControlNet links
to route messages to devices on other networks. The modules also monitor
and control I/O modules located remotely from CompactLogix controllers.
The 1768-CNB and 1768-CNBR ControlNet modules:
• provide messaging data for configuration and programming.
• support operator interfaces and uploading and downloading.
• support I/O bridging.
• support the transfer of scheduled data via produced/consumed tags.
• support unscheduled MSG instruction communication with other
ControlNet nodes.
• support local communication network access through the network
access port (NAP).
• support redundant media (1768-CNBR module only).
In this example:
• the controllers produce and consume tags.
• the controllers initiate MSG instructions that send and receive data or
configure devices.
• the personal computer uploads or downloads projects to the controllers.
• the personal computer configures devices on the ControlNet network
and the network itself.