I want to send the value in payload to a node, i can send a fixed value, but can't figure out how to send the payload value.
What do I miss?
I'm not sure what you are asking. You send messages between nodes and they can have whatever properties and values you set on them.
Can you explain a bit more what you are trying to do? What is the relevance of the screenshot you've shared?
I can try.
For test purpose i inject a value, when i find the right way i will read a Modbus value and write it to a IHC ( Home control system).
I have tried to change "msg.payload" with a number and my node-red can send the fixed value to the IHC.
I want the to send a floating point msg.
This one works
generally if you want a node to use a value from the flow you need to construct that part before the config screen and leave that part blank.
e.g in the http-request node you can either add the URL in the http-request node OR pass the URL to the http-request node as msg.url.
so you could try creating the msg.Data before the node in a function node. and leaving that part of the node properties blank.
But it does depend on the node, and you haven't said which node you are using...