Rockwell Automation DAG6.5.8 APPLICATION GUIDE SCADA SYSTEM - Manual (Page 254)

Publication AG-UM008C-EN-P - February 2005
7-28 Configuring Logix Controllers
Messaging Messaging can occur between:
•
a master station and a slave station,
•
a slave station and its master station (see Polled
Report-by-Exception),
•
slave stations or between two controllers connected via a
point-to-point link.
Master Station to Slave Station
A Logix master station communicates with the slave stations that are
connected to it via modems in a point-to-multipoint configuration. A
master station sends a slave station message to receive status or issue
commands. For sample messaging ladder logic to use as a guide when
using Standard or Message-based Polling Modes, see page E-19.
Polled Report-by-Exception
Slave stations can gather information from the I/O points they are
responsible for and can send any anomalous readings to the master
station. To do this, write ladder logic in the slave station to monitor
certain conditions and send the data in an MSG instruction to the
master station. For sample messaging ladder logic to use as a guide
when using a Logix as a slave, see page E-21.
9. Enter in the path
to the remote
controller.