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Sorry for my bad English.

I am trying to read data by the Modbus RTU method (library: minimalmodbus) but have a problem.

This is my 'Modbus Poll' display.

I would like to read data by using minimalmodbus.

import minimalmodbus
import serial
instrument = minimalmodbus.Instrument('COM5', 1)  # port name, slave address (in decimal)
instrument.serial.port = 'COM5'                     # this is the serial port name
instrument.serial.baudrate = 9600         # Baud
instrument.serial.bytesize = 8
instrument.serial.parity   = serial.PARITY_NONE
instrument.serial.stopbits = 1
instrument.serial.timeout  = 0.1        # seconds
instrument.address = 1                         # this is the slave address number
instrument.mode = minimalmodbus.MODE_RTU   # rtu or ascii mode
result = instrument.read_float(0, 4, 20)
print(result)
But, I keep failing.
Can please someone help me with how to read data?
                To replicate your modbus poll setup, you'll want to use read_registers(registeraddress: int, number_of_registers: int, functioncode: int = 3), for your case instrument.read_registers(0, 20, 4), this will return a list of the twenty input registers.
– import random
                Aug 19, 2022 at 7:14
        
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