MODBUS - despite being very old - is a common and widely used protocol in industrial applications for connection sensors, plc's and machines. The MODBUS protocol can be seen as an early client/server protocol, the client (MODBUS master) requests data and the server (MODBUS slave) replies. E.g. for a data reuest, the master specifies the MODBUS register(s) and gets the content of the register(s). There are no semantics defined here.
There are lots of MODBUS software libraries available for different platforms, MODBUS variants (RTU,TCP/IP,...), ...
My goal is to write a software for multiple (standard) industry devices that are talking MODBUS.
My question are:
- Is there is a global directory of register definitions for MODBUS devices?
- Is there a software with built-in register definitions for many (thousand, even million) MODBUS devices?
Free (open source) libraries are preferred.