Rockwell Automation DAG6.5.8 APPLICATION GUIDE SCADA SYSTEM User Manual
Page 390
Publication AG-UM008C-EN-P - February 2005
E-8 Sample Ladder Logic
PLC-5 and MicroLogix 1100/1200/1500 DF1 Half-Duplex Master Standard Mode,
Master-initiated MSG
PLC-5 DF1 Half-Duplex Master - Standard Mode, Master-initiated MSG
Each MSG is assigned a "Finished" bit and a "Disable" bit. Up to 17 MSG's are triggered simultaneously, but cannot be retriggered until all enabled MSG's have completed either done or in error. After all enabled MSG's have
completed, a time delay is inserted before retriggering. If no time delay is desired (retriggering the MSG's as fast as possible), then set the T4:0 timer preset to zero. This example has 21 messages. You must delete or add
"MSG Finished" bits and "Disable MSG" bits to match the number of messages in your application.
0000
B3:16
1
MSG #1
Finished
B3:0
1
Disable
MSG #1
B3:16
2
MSG #2
Finished
B3:0
2
Disable
MSG #2
B3:16
3
MSG #3
Finished
B3:0
3
Disable
MSG #3
B3:16
4
MSG #4
Finished
B3:0
4
Disable
MSG #4
B3:16
5
MSG #5
Finished
B3:0
5
Disable
MSG #5
B3:16
6
MSG #6
Finished
B3:0
6
Disable
MSG #6
B3:16
7
MSG #7
Finished
B3:0
7
Disable
MSG #7
B3:16
8
MSG #8
Finished
B3:0
8
Disable
MSG #8
B3:16
9
MSG #9
Finished
B3:0
9
Disable
MSG #9
B3:16
10
MSG #10
Finished
B3:0
10
Disable
MSG #10
B3:16
11
MSG #11
Finished
B3:0
11
Disable
MSG #11
B3:16
12
MSG #12
Finished
B3:0
12
Disable
MSG #12
B3:16
13
MSG #13
Finished
B3:0
13
Disable
MSG #13
B3:16
14
MSG #14
Finished
B3:0
14
Disable
MSG #14
B3:16
15
MSG #15
Finished
B3:0
15
Disable
MSG #15
B3:17
0
MSG #16
Finished
B3:1
0
Disable
MSG #16
B3:17
1
MSG #17
Finished
B3:1
1
Disable
MSG #17
B3:16
0
MSG #1-17
Finished
B3:0
0
Trigger
MSG #18-34
B3:16
0
MSG #1-17
Finished
0001
B3:16
0
MSG #1-17
Finished
B3:17
2
MSG #18
Finished
B3:1
2
Disable
MSG #18
B3:17
3
MSG #19
Finished
B3:1
3
Disable
MSG #19
B3:17
4
MSG #20
Finished
B3:1
4
Disable
MSG #20
B3:17
5
MSG #21
Finished
B3:1
5
Disable
MSG #21
EN
DN
TON
Timer On Delay
Timer
T4:0
Time Base
1.0
Preset
10<
Accum
3<
TON
Trigger MSG's
Delay Timer
The following two rungs are the MSG control rungs - they should be replicated for further messages. For MSG #18-34, replace XIC T4:0/DN with XIC B3:0/0. Be sure to use the proper "Active Node Bit" from B11/0-B11/254
for nodes 0-254 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.
0002
B3:0
1
Disable
MSG #1
EN
DN
ER
MSG
Read/Write Message
Control
MG9:1
Setup Screen
MSG
MSG #1 to Node #1
0003
MG9:1
EN
MSG #1
Enabled
MG9:1
DN
MSG #1
Done
MG9:1
ER
MSG #1
Error
B3:16
1
MSG #1
Finished
T4:0
DN
MSG
Delay
Done
B11:0
1
Node
#1
Active
U
MG9:1
EN
MSG #1
Enabled
0004
B3:0
2
Disable
MSG #2
EN
DN
ER
MSG
Read/Write Message
Control
MG9:2
Setup Screen
MSG
MSG #2 to Node #2
0005
MG9:2
EN
MSG #2
Enabled
MG9:2
DN
MSG #2
Done
MG9:2
ER
MSG #2
Error
B3:16
2
MSG #2
Finished
T4:0
DN
MSG
Delay
Done
B11:0
2
Node
#2
Active
U
MG9:2
EN
MSG #2
Enabled