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Rockwell Automation DAG6.5.8 APPLICATION GUIDE SCADA SYSTEM User Manual

Page 385

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Publication AG-UM008C-EN-P - February 2005

Sample Ladder Logic E-3

The following two rungs are the MSG control rungs - they should be replicated for further messages. Be sure to use the proper "Active Node Bit" from
S:67/0-S:82/14 for nodes 0 to 254 based on the Target Node Address in the MSG. This assures that messages will not be triggered to nodes that are
currently inactive (did not respond the last time they were polled by the Master). This "automatically" helps prevent unnecessary message retries to
non-communicating nodes.

0001

B3:0

1

Disable
MSG #1

EN

DN

ER

MSG

Read/Write Message
Type

Peer-To-Peer

Read/Write

Read

Target Device

500CPU

Local/Remote

Local

Control Block

N11:0

Control Block Length

14

Setup Screen

MSG

MSG #1 to Node #1

0002

N11:0

15

MSG #1
Enabled

N11:0

13

MSG #1
Done

N11:0

12

MSG #1
Error

B3:16

1

MSG #1
Finished

T4:0

DN

MSG
Delay
Done

S2:67

1

Node
#1
Active

U

N11:0

15

MSG #1
Enabled

0003

B3:0

2

Disable
MSG #2

EN

DN

ER

MSG

Read/Write Message
Type

Peer-To-Peer

Read/Write

Read

Target Device

500CPU

Local/Remote

Local

Control Block

N12:0

Control Block Length

14

Setup Screen

MSG

MSG #2 to Node #2

0004

N12:0

15

MSG #2
Enabled

N12:0

13

MSG #2
Done

N12:0

12

MSG #2
Error

B3:16

2

MSG #2
Finished

T4:0

DN

MSG
Delay
Done

S2:67

2

Node
#2
Active

U

N12:0

15

MSG #2
Enabled

0005

B3:0

3

Disable
MSG #3

EN

DN

ER

MSG

Read/Write Message
Type

Peer-To-Peer

Read/Write

Read

Target Device

500CPU

Local/Remote

Local

Control Block

N13:0

Control Block Length

14

Setup Screen

MSG

MSG #3 to Node #3