Rockwell Automation RECOMM-DNET DeviceNet Adapter for use with DPI AC Drives User Manual
Page 79
Using Explicit Messaging
7-13
Ladder Logic Program
Important: To originate a scanner transaction, use a copy operation
to M0:[slot number]:224. Then, use a copy operation to
read M1:1.224 for the result. If more than one message
is enabled, use the TXID to determine which message
you are reading.
Figure 7.9 – Sample SLC Ladder Logic Program
0000
B3:0
0
COP
#N20:10
#M0:1:224
32
U
B3 :0
0
Initiate
Explicit
Message
0001
I:1.0
15
1747-SDN
Explicit
Message
Response
Available
COP
Copy File
Source
#M1:1:224
Dest
#N20:50
Length
32
Explicit
Message
Response
EQU
Equal
Source A
N20:10
257 <
Source B
N20:50
257 <
MVM
Mask Move
Source
N20:0
4<
Mask
00FFh
255 <
Dest
M0:1.224
?<
Explicit
Message
0002
END
Initiate
Explicit
Message
Explicit
Message
Copy File
Source
Dest
Length
When B3:0/0 is set to true, this rung will
copy the 32 words of Explicit Message from
the buffer at N20:10 to M0-File Explicit
Message buffer. The scanner will send the
message out over DeviceNet.
When I:1.0/15 is set to true and the Explicit
Message Response has been received in the
M1-File, this rung performs the following:
- Copies the response message into N10:50.
- Copies a command of four (4) into the
M1-File.The four (4) commands the 1747-SDN
scanner to discard the response data so that the
buffer can be used for the next message
response.