Rockwell Automation Allen-Bradley ControlNet 1734-ACNR User Manual page 155

ControlNet Overview B-7
Control of Scheduled I/O
Scheduled connections allow you to send and to receive data repeatedly at a
predetermined rate. You can use the 1756-CNB or the 1756-CN2 module to
control scheduled I/O when you use it in conjunction with a ControlLogix
controller. When you place the module in the I/O configuration list of a
ControlLogix controller and configure a second ControlLogix chassis, with a
remote 1756-CNB or 1756-CN2 module, on the same ControlNet network,
you can perform remote control operations on the I/O, or to a second
controller, in the second chassis.
In this situation, the ControlLogix controller and the 1756-CN2 module in the
local chassis together act as a scanner, while the 1756-CN2 module in the
remote chassis with the I/O plays the role of an adapter.
Publication CNET-UM001C-EN-P - November 2005