I am interacting with an "Arduino-based PLC" (If it can be called "PLC") with Node-RED via MODBUS-TCP (I installed node-red-contrib-modbusTCP).
I am using in the same flow one node that writes both Coils and Holding Registers, and several nodes for reading (each one) coils, discrete inputs, holding registers and input registers, from the same slave device.
The problem that I have is that lots of times no all the nodes shows the status "connected" and I have to restart node-RED to try they to connect.
Every time that I make changes and deploy the flow, most of the nodes lose the conection and I have to close Node-RED and open it again (and some times I have to do that several times until all the nodes are succesfully connected).
I would like to know the reasons why the same "server" can be connected with some nodes and not with others.
I guess that I could read all the data types with only one node using the inputs of the Read node (each input message would override the function, the address and the quantity), but I don't know what happens with the "poll rate' every time that I inject an input through the read node.
Is it possible to annul the poll-rate so that I only read the Modbus content when I want?
I want to apologise because my english is quite rusty, and furthermore I am very newbie not only in Node-RED but in any thing related to programming...