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Creating Modbus Server Communication with Client

See original GitHub issue

Issue Description

I want to create a modbus server (with local host : ip address : - same as the system) and the modbus client has (ip address : My client application is running and i am creating the modbus server application with the umodbus server application. Data exchange of 32 bits (either read or write for testing purpose). Slave Id : 1 and Port : 255

How do i configure python umodbus server with server able to read and write data into the client ip address

Here is the umodbus server application -

#!/usr/bin/env python
# scripts/examples/
import random
import logging
from socketserver import TCPServer
from collections import defaultdict

from umodbus import conf
from umodbus.server.tcp import RequestHandler, get_server
from umodbus.utils import log_to_stream

# Create Random Values
rndata = []
for i in range(32):

# Add stream handler to logger 'uModbus'.

# A very simple data store which maps addresss against their values.
data_store = defaultdict(int)

# Enable values to be signed (default is False).

TCPServer.allow_reuse_address = True
app = get_server(TCPServer, ('', 255), RequestHandler)

@app.route(slave_ids=[1], function_codes=[3, 4], addresses=list(range(0, 32)))
def read_data_store(slave_id, function_code, address):
    """" Return value of address. """
    return data_store[address]

@app.route(slave_ids=[1], function_codes=[6, 16], addresses=list(range(0, 32)))
def write_data_store(slave_id, function_code, address, value):
    """" Set value for address. """
    data_store[address] = value

# Configuring the Data
rdata1 = read_data_store(1,4,3)
rdata2 = read_data_store(1,4,24)

if __name__ == '__main__':

Issue Analytics

  • State:closed
  • Created 5 years ago
  • Comments:23

github_iconTop GitHub Comments

OrangeTuxcommented, Oct 14, 2020

@rahimdzb Modbus requests for slave 1, using function code 3 or 4, addressing registers 0 till 32 will be executed by this callback.

rahimdzbcommented, Oct 27, 2020

Sir can you tell me what’s happening exactly in this function ( get_server(Tcpserver,(‘localhost’,502),RequestHandler)

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