Hi Xiangdong, The example "ns=2;s=HelloWorld/ScalarTypes/Double" is just an example address. It was taken from the Eclipse Milo OPC UA server example.
For your case the address would be "ns=3;i1002" On a somewhat related note, you may also be interested in the OPC UA server https://github.com/apache/plc4x/tree/develop/plc4j/integrations/opcua-server https://plc4x.apache.org/users/integrations/eclipse-milo.html Kind Regards Ben On Thu, Dec 17, 2020 at 8:18 PM Xiangdong Huang <[email protected]> wrote: > Hi Ben, > > Thanks for your kindly and quickly reply. > > One more question, > > I am using Prosys OPC UA Simulation Server, and the NodeId is: ns=3;i=1002, > NodeClass is Variable, DataType is Double. > So, how to define the field address in PLC4x? > I checked [1], the example is: DOUBLE_IDENTIFIER = " > ns=2;s=HelloWorld/ScalarTypes/Double"; > What is the meaning of "HelloWorld/ScalarTypes", or, where I can confirm > how to get the needed info of DOUBLE_IDENTIFIER from Prosys OPC UA > Simulation Server? > > [1] > > https://github.com/apache/plc4x/blob/develop/plc4j/drivers/opcua/src/test/java/org/apache/plc4x/java/opcua/ManualPLC4XOpcua.java > > Best, > ----------------------------------- > Xiangdong Huang > School of Software, Tsinghua University > > 黄向东 > 清华大学 软件学院 > > > Ben Hutcheson <[email protected]> 于2020年12月18日周五 上午8:41写道： > > > Hi Xiangdong, > > > > Yes you are right, the example in the opc ua section doesn't look right. > I > > can take a look at updating it tomorrow. > > > > Your best bet would be to follow the getting started - java section. > > https://plc4x.apache.org/users/getting-started/plc4j.html > > > > the connection string format for the opc ua driver is > > > > opcua:tcp://127.0.0.1:12686/milo?discovery=false > > > > (Discovery option being optional.) > > > > Also if you are comfortable the 0.8.0-SNAPSHOT is more stable. > > > > You'll have to add the repository to your pom.xml file though. > > > > <repositories> > > > <repository> > > > <id>apache.snapshots</id> > > > <name>Apache Snapshot Repository</name> > > > <url>https://repository.apache.org/snapshots</url> > > > <releases> > > > <enabled>false</enabled> > > > </releases> > > > </repository> > > > </repositories> > > > > > > > Specifically with the OPC UA driver we are in the process of merging an > > update to the 0.8.0-SNAPSHOT to support specifying the data type in the > > address field. > > > > The current address format is:- > > > > ns=2;s=HelloWorld/ScalarTypes/Boolean > > > > This will change to:- > > > > ns=2;s=HelloWorld/ScalarTypes/Boolean:BOOL > > > > With the update, however the :BOOL datatype will be optional, unless > > you need to read/write unsigned values. > > > > If you have any more questions let us know. > > > > Kind Regards, > > > > Ben > > > > > > On Thu, Dec 17, 2020 at 6:59 PM Xiangdong Huang <[email protected]> > > wrote: > > > > > Hi, > > > > > > Today I followed the User guide on the website to run PlC4x to collect > > > data, and then find an issue of the example [1]. > > > > > > In the reading data example, the example creates an > opcuaReadConnection, > > > and then uses opcuaConnection. What is worse, opcuaConnection has no > > such a > > > read() method but the example calls it.. (version 0.7.0) > > > > > > I think the API may change but the document did not keep to update. > > > > > > [1] https://plc4x.apache.org/users/protocols/opc-ua.html > > > > > > Best, > > > ----------------------------------- > > > Xiangdong Huang > > > School of Software, Tsinghua University > > > > > > 黄向东 > > > 清华大学 软件学院 > > > > > >
