Rockwell Automation 1797-OE8 FLEX Ex Analog Modules User Manual - Manual (Page 51)

Publication 1797-6.5.1 - May 2005
Input, Output, and Configuration Files for the Analog I/O Modules on the ControlNet Network 4-3
Communication Over the
FLEX Ex Backplane One 1797-ACNR15/B ControlNet Ex adapter can interface up to eight
terminal base units with installed FLEX Ex modules, forming a FLEX Ex
system of up to eight slots.
The adapter communicates to other network system components (typically
one or more controllers or scanners, and/or programming terminals) over the
ControlNet network. The adapter communicates with its I/O modules over
the FLEX Ex backplane.
Configuration data is not continuously updated to the module.
Scheduled Data-Transfer
Scheduled data transfer:
• is continuous.
• is asynchronous to the controller program scan.
• occurs at the actual rate displayed in the Actual Packet Interval field on
the programming software ControlNet I/O mapping (monitor) screen
Unscheduled Data-Transfer
Unscheduled operations include:
• unscheduled non-discrete I/O data transfers–through ControlNet I/O
Transfer (CIO) instructions
• peer-to-peer messaging–through message (MSG) instructions
• messaging from programming devices
I/O Module I/O Module I/O Module
Configuration Configuration Configuration
Inputs Inputs Inputs
Status
Outputs
Status Status
Outputs Outputs
Read
Words
Write
Words
0
X Slot 0 Slot 1 Slot 7
Networ
ControlNet Ex
Adapter
Read
Write
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