Manual
7-14
DeviceNet Communications Module
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.
For the I/O message portion of this sample ladder program, see
figure 6.6.
Figure 7.9 – Sample SLC Ladder Logic Program
Explicit Messaging Example
When B3:2/0 is set ON, this rung will copy the 32 words of Explicit Message from
the buffer at N9:10 to the M0 File Explicit Message buffer. The scanner will send
the message out over DeviceNet.
0014
B3:2
0
COP
Copy File
Source #N9:10
Dest #M0:1.224
Length 32
COP
U
B3:2
0
When I:1.0/15 is ON (response to the explicit message is available), the response
message is copied into N9:50. A "4" command is copied into the M0 file, which
commands the 1747-SDN to discard the response data so that the buffer can be used
for the next message.
0015
I:1
15
1747-SDN
COP
Copy File
Source #M1:1.224
Dest #N9:50
Length 32
COP
EQU
Equal
Source A N9:10
257<
Source B N9:50
257<
EQU
MVM
Masked Move
Source N9:0
4<
Mask 00FFh
255<
Dest M0:1.224
?<
MVM
0016
END