Slc messaging, Figure 6.4 slc messaging example, Using devicenet explicit messages 6-9 – Rockwell Automation 1203-GK5 DeviceNet Communications Module FRN 1.xxx-3.xxx User Manual

Page 77

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Using DeviceNet Explicit Messages

6-9

SLC Messaging

Figure 6.4 shows an example message in the SLC ladder logic
program started in Chapter 5, Creating a Ladder Logic Program.

Figure 6.4
SLC Messaging Example

Important: To originate a scanner transaction, you must use a copy
operation to M0:[slot number]:224. Then, use a copy operation to
read M1:1.224 for the results. If you have more than one message
enabled, you will have to use the TXID to determine which message
you are reading.

When B3:0/0 is set true, this rung will copy the 32 words of the Esplicit Message from the buffer at N20:10 to the M0-File Explicit
Message buffer.

The 1747-SDN will send the message out over DeviceNet.

0000

B3:0

0

Initiate
Explicit
Message

COP

Copy File
Source

#N20:10

Dest

#M0:1.224

Length

32

COP

Explicit
Message

U

B3:0

0

Initiate
Explicit
Message

When I:1.0/15 is true, and the Explicit Message response has been received and is in the M1-File, this rung:

1) Copies the response message into N10:50
2) Copies a command byte of 4 into the M1-File (commands the 1747-SDN scanner to discard the response data so

that the buffer can be used for the next available response message)

0001

I:1.0

15

1747-SDN

Explicit
Message
Response
Available

COP

Copy File
Source

#M1:1.224

Dest

#N20:50

Length

32

COP

Explicit
Message
Response

EQU

Equal
Source A

N20:10

257 <

Source B

N20:50

257 <

EQU

MVM

Masked Move
Source

N20:0

4<

Mask

00FFh

255 <

Dest

M0:1.224

?<

MVM

Explicit
Message

0002

END

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