To test the example, you can copy the following code and paste it into an empty project, of course the CODESYS program must be running SimpleUPCUA. Remember to change the IP address of the OPCUA Server.
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Neue,sans-serif"},"themeState":{"base-color":{"default":"#0094CE","value":"#0094CE","edited":false},"page-titlebar-backgroundColor":{"value":"#0094CE","edited":false},"page-backgroundColor":{"value":"#fafafa","edited":false},"page-sidebar-backgroundColor":{"value":"#ffffff","edited":false},"group-textColor":{"value":"#1bbfff","edited":false},"group-borderColor":{"value":"#ffffff","edited":false},"group-backgroundColor":{"value":"#ffffff","edited":false},"widget-textColor":{"value":"#111111","edited":false},"widget-backgroundColor":{"value":"#0094ce","edited":false},"widget-borderColor":{"value":"#ffffff","edited":false},"base-font":{"value":"-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen-Sans,Ubuntu,Cantarell,Helvetica Neue,sans-serif"}},"angularTheme":{"primary":"indigo","accents":"blue","warn":"red","background":"grey"}},"site":{"name":"Node-RED Dashboard","hideToolbar":"false","allowSwipe":"false","lockMenu":"false","allowTempTheme":"true","dateFormat":"DD/MM/YYYY","sizes":{"sx":48,"sy":48,"gx":6,"gy":6,"cx":6,"cy":6,"px":0,"py":0}}},{"id":"fefa668f.751fc8","type":"ui_tab","z":"","name":"Main","icon":"dashboard","order":1,"disabled":false,"hidden":false},{"id":"1c67e3b2.585c7c","type":"ui_group","z":"","name":"My Dashboard","tab":"fefa668f.751fc8","order":1,"disp":true,"width":"6","collapse":false},{"id":"a9407375.ad7b","type":"inject","z":"78a821d6.71cc3","name":"","topic":"","payload":"1","payloadType":"num","repeat":"1","crontab":"","once":false,"onceDelay":0.1,"x":110,"y":300,"wires":[["a9cc134f.3c259"]]},{"id":"a9cc134f.3c259","type":"OpcUa-Item","z":"78a821d6.71cc3","item":"ns=4;s=|var|CODESYS Control for Raspberry Pi SL.Application.PLC_PRG.Counter","datatype":"UInt32","value":"","name":"","x":320,"y":300,"wires":[["3b553ad1.95c7e6"]]},{"id":"3b553ad1.95c7e6","type":"OpcUa-Client","z":"78a821d6.71cc3","endpoint":"a5fa9e01.cfaf6","action":"read","deadbandtype":"a","deadbandvalue":1,"time":10,"timeUnit":"s","certificate":"n","localfile":"","name":"","x":520,"y":300,"wires":[["954e9722.cdd3a8","a5077176.e41b4"]]},{"id":"954e9722.cdd3a8","type":"ui_text","z":"78a821d6.71cc3","group":"1c67e3b2.585c7c","order":0,"width":0,"height":0,"name":"","label":"Counter","format":"{{msg.payload}}","layout":"row-spread","x":700,"y":300,"wires":[]},{"id":"a978aa03.2e7fd8","type":"ui_switch","z":"78a821d6.71cc3","name":"","label":"DOCommand","tooltip":"","group":"1c67e3b2.585c7c","order":1,"width":0,"height":0,"passthru":true,"decouple":"false","topic":"","style":"","onvalue":"true","onvalueType":"bool","onicon":"","oncolor":"","offvalue":"false","offvalueType":"bool","officon":"","offcolor":"","x":120,"y":180,"wires":[["2df7e872.48a7d8"]]},{"id":"2df7e872.48a7d8","type":"OpcUa-Item","z":"78a821d6.71cc3","item":"ns=4;s=|var|CODESYS Control for Raspberry Pi SL.Application.PLC_PRG.DOCommand","datatype":"Boolean","value":"","name":"","x":320,"y":180,"wires":[["69afc737.ac9a18"]]},{"id":"69afc737.ac9a18","type":"OpcUa-Client","z":"78a821d6.71cc3","endpoint":"a5fa9e01.cfaf6","action":"write","deadbandtype":"a","deadbandvalue":1,"time":10,"timeUnit":"s","certificate":"n","localfile":"","name":"","x":520,"y":180,"wires":[["8dd2298c.0a7b98"]]},{"id":"8dd2298c.0a7b98","type":"debug","z":"78a821d6.71cc3","name":"","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","x":710,"y":180,"wires":[]},{"id":"a5077176.e41b4","type":"debug","z":"78a821d6.71cc3","name":"","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","x":710,"y":240,"wires":[]},{"id":"f030e24.9615b2","type":"OpcUa-Item","z":"78a821d6.71cc3","item":"ns=4;s=|var|CODESYS Control for Raspberry Pi SL.Application.PLC_PRG.DIStatus","datatype":"Boolean","value":"","name":"","x":320,"y":100,"wires":[["5fc5f389.f3337c"]]},{"id":"5fc5f389.f3337c","type":"OpcUa-Client","z":"78a821d6.71cc3","endpoint":"a5fa9e01.cfaf6","action":"read","deadbandtype":"a","deadbandvalue":1,"time":10,"timeUnit":"s","certificate":"n","localfile":"","name":"","x":520,"y":100,"wires":[["135032e8.ef2d5d"]]},{"id":"a10173b4.131ff","type":"inject","z":"78a821d6.71cc3","name":"","topic":"","payload":"1","payloadType":"num","repeat":"1","crontab":"","once":false,"onceDelay":0.1,"x":110,"y":100,"wires":[["f030e24.9615b2"]]},{"id":"135032e8.ef2d5d","type":"ui_text","z":"78a821d6.71cc3","group":"1c67e3b2.585c7c","order":3,"width":"1","height":"1","name":"Di00","label":"","format":"<font color={{(msg.payload?\"green\":\"lightgrey\")}}><i class=\"fa fa-lightbulb-o fa-2x\"></i></font><br/><font size=\"-2\">Di00</font>","layout":"col-center","x":710,"y":100,"wires":[]}]