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Figure 26. Subscribing to data changes of the ETH3 ::: N_TXBYTE node of the OPC-SJA1105 server
In the FreeOpcUa GUI, it is possible to create subscriptions to Data Changes on port counters of interest (by right-clicking on the
individual nodes in the Address Space).
A dedicated OPC client might run custom code upon receiving Data Change notifications from the server, whereas the FreeOpcUa
GUI only displays the updated values.
Figure 27. Data change notification
The preceding figure shows the Data Change Subscriptions to two counters: the Tx Frames of the L2 switch towards the LS1021,
and the Tx Bytes towards chassis port ETH5.
NXP Semiconductors
OPC UA
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