Rockwell Automation 2755-SNx Adaptascan Bar Code Readers User Manual
Page 248
12–27
Communicating with a PLC-5 Processor on a DeviceNet Network using Explicit Messaging
Publication 2755-6.8
Notes on using Explicit Messaging
•
You can send messages sequentially from the PLC-5 to different
bar code readers, but the response will not update properly (when
the response is read in N25:0).
•
The TXID byte does not need to be incremented, although you
may not know where the response came from.
•
To receive the correct response from the command sent from the
PLC-5 you must:
1. Send command down, matchcode download (TXID=11).
2. Send a 03 in the status command. Refer to page 12–21 for
more information.
3. Increment TXID to 12.
4. Send command down, turn on LED 1 (TXID=12).
5. View N25:0 for response to step 4.
6. Confirm that TXID=12. If your response is 90, the command
was sent correctly. If you receive a 94, the command was not
sent correctly.
•
If an incorrectly formatted command is sent from the PLC-5, you
must send a 03 in the status command byte in order for the system
to operate properly.