If there is a runtime + webvisu running at the .101 then the link should be: http://192.168.1.101:8080/webvisu.htm
Maybe shared memory is an opinion for you to give it a try: https://content.helpme-codesys.com/en/CODESYS%20Examples/_ex_cds_shared_memory_communication.html
you can get the help by yourself in the helpme site: https://content.helpme-codesys.com/en/CODESYS%20Development%20System/_cds_operator_move.html
rmaas: how do you get the reference of the slave?
learn to program in structured text or CFC and forget this antique ladder logic.. I'm not firm to do that in ladder
post a screenshot of the ladder and the error message. I'm not able to have a lock at your monitor actually :-)
the magic option is named "Use CurrentVisu variable" activate this option in the Visualization Manager an have a look: https://help.codesys.com/webapp/_visu_obj_manager;product=core_visualization;version=3.5.14.0 if your button is pressed, "feed" the string varable VisuElems.CurrentVisu := 'visu1'; with the correct name of the depending visu. alternative: place a frame element at a empty main visu, konfigure all visus to be shown by this frame. With setting the switching variable of the frame to...
to modify and change the color of this icons from symbols lib I placed it in a visu. After download to the device, I uploaded the SVG files and saved it local. Now I was able to modify them with inkscape and import it to my own imagepool in the project :-)