Balluff BIS M-370-000-A02, Manual, Page: 89 / 198

BIS M-62_ MANUAL
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5.8 VERIFYING DATA EXCHANGE WITH RSLOGIX 5000
At this point, communication between the BIS M-626 and the PLC should be properly
configured and a connection established. You can verify the exchange of information
between devices using RSLogix 5000.
Figure 52 - RSLogix 5000
5.8.1
Industrial Ethernet (IND)
Handshaking
To ensure that messages to and from the BIS M-626 are properly delivered and received, a
handshaking mechanism has been implemented that uses a pair of dedicated words in the
exchange. The first two words in each
Controller Tag are dedicated to handshaking.
When new information is generated, the producing device ( Data Producer ) will increment a
counter in one of the Controller Tags . After identifying the new data, the consuming device
( Data Consumer ) will copy that same counter value to a different Controller Tag location,
which lets the Data Producer know that the information has been processed by the Data
Consumer.
WRITE TAG (where responses are written by the Cobalt)
EMS_Write1 [0] = (2) the Cobalt copies counter here to ACK
EMS_Write1 [1] = (3) the Cobalt increments this counter to signal response available
EMS_Write1 [2] = Data Size
EMS_Write1 [3-102] = Data
READ TAG (where commands are retrieved by the Cobalt)
EMS_Read1 [0] = (4) PLC copies the counter here to ACK the response
EMS_Read1 [1] = (1) PLC increments this counter after writing a command
EMS_Read1 [2] = Data Size
EMS_Read1 [3-102] = Data