Rockwell Automation 1794-AENTR_AENTRXT FLEX I/O Dual Port EtherNet/IP Adapter Modules - Manual (Page 13)

Publication 1794-UM066A-EN-P - February 2012
Overview of FLEX I/O and Your Redundant EtherNet/IP Adapter Module 5
the 8 I/O modules. If you use a rack-optimized connection to transfer the data,
you only need a single connection – the connection to the adapter.
Refer to the EtherNet/IP Embedded Switch Technology Application Guide,
publication number
ENET-AP005 , for more information on connections.
Mixing Rack Optimized and Direct Connections
You can mix communication formats for different I/O modules communicating
through the same adapter. I/O modules set up to use rack optimization will
communicate at the rate of the requested packet interval (RPI) configured for the
1794-AENTR or 1794-AENTRXT adapter. I/O modules configured for direct
communication will communicate at their own set RPIs and ignore the
adapter RPI.
Chapter Summary This chapter briefly described the FLEX I/O system, the FLEX I/O dual port
EtherNet/IP adapters, and the basic adapter features. Read the next chapter to
learn how to physically install the adapters and connect them to the EtherNet/IP
network.
IMPORTANT Although rack optimized connections offer an efficient way to use
resources, there are a few limitations on their use:
•
You can only use rack optimized connections to send data to and
from discrete I/O modules. Analog I/O requires direct
connections.
•
Rack optimized connections can contain I/O data and status
information only. Additional module information, such as
diagnostics, is not available through a rack-optimized connection.
•
All data is sent at the same time at the RPI rate of the adapter.