Examples, Examples -6, Plc messaging – Rockwell Automation 1336-GM6 Enhanced DeviceNet Communications Module User Manual
Page 76

7-6
Using DeviceNet Explicit Messaging
Examples
The following examples show messages used with the ladder logic
programs begun in Chapter 6, Ladder Logic Programming.
PLC Messaging
Figure 7.3, started in Chapter 6, Ladder Logic Programming, shows
an example PLC ladder logic program that sends an explicit message.
The message sent is contained in N30, beginning at word 0. The
response data will appear in N30 starting at word 70.
Figure 7.3
PLC Messaging Example
!
ATTENTION: The example ladder logic program
shown in this manual is intended solely for purpose of
example. Because there are many variables and
requirements associated with any particular installation,
Rockwell Automation does not assume responsibility or
liability (to include intellectual property liability) for
actual use based upon the example shown in this
publication.
0000
I:000
17
ONS
B3:0
0
EN
DN
ER
BTW
Block Transfer Write
Module Type 1771-SDN DeviceNet Scanner Module
Rack
000
Group
0
Module
0
Control Block
BT20:2
Data File
N30:0
Length
64
Continuous
No
BTW
MOV
Move
Source
0
0<
Dest
N30:70
257<
MOV
0001
BT20:2
DN
CMP
Comparison
Expression N30:70 <> N30:0
CMP
BT20:3
EN
EN
DN
ER
BTR
Block Transfer Read
Module Type 1771-SDN DeviceNet Scanner Module
Rack
000
Group
0
Module
0
Control Block
BT20:3
Data File
N30:70
Length
64
Continuous
No
BTR
0002
END