Hello world, i wanna ask how to read data from plc to node red. i used the RS485 usb converter to connect it to Raspberry Pi. And i just install the modbus rtu palette for its communication but, how to read all data from the rs485 to node red . i also got this /dev/ttyUSB0
First thought I had was if that RS485 to USB converter is compatible with Linux. It very well may not.
You should be able to pull a serial in/out node in and send it some commands and see if you get a response.
There is a modbus message structure you would have to inject.https://www.picotech.com/images/uploads/library/topics/_med/modbus-frame-structure.jpg
Try the node-red-contrib-modbus package -- will have everything you need for both Modbus RTU and TCP.
I already installed the palette, but i dont know how to setup its node flow. And should i need to get its serial code first for i/o data?
Have you tried the wiki? https://github.com/biancode/node-red-contrib-modbus/wiki