modbus

I have to control a modbus device with a serial interface. I've got not experience with modbus. But my short research revealed several modbus libraries pymodbus MinimalModbus Modbus-tk uModbus What are the advantages/disadvantages, are there even better alternatives? About the same time I faced the same problem - which library to choose for python modbus master implementation but in my case for serial communication (modbus RTU) so my observations are only valid for modbus RTU. In my examination I didn't pay too much attention to documentation but examples for serial RTU master were easiest to

I have one energy meter and i am trying to retrieve voltage, freq values from meter on raspberry pi uart over RS485 My connections for raspberry pi and rs485 are as follows Rs485 DI - Tx of raspberry pi Rs485 R0 - Rx of raspberry pi Rs485 DE/RE -Pin 7 of raspberry pi my code is as follows: import serial import RPi.GPIO as GPIO from pymodbus.client.sync import ModbusSerialClient as ModbusClient from pymodbus.register_read_message import ReadInputRegistersResponse from pymodbus.register_read_message import ReadInputRegistersRequest import logging logging.basicConfig() log = logging.getLogger()