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Questions tagged [modbus-tcp]

A messaging structure developed by Modicon. It is used to establish master-slave/client-server communication between intelligent devices.

A messaging structure developed by Modicon in 1979. It is used to establish master-slave/client-server communication between intelligent devices. (from http://www.modbus.org/faq.php)

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Modbus RTU over TCP - communication closed

I am trying to connect Home Assistant to a Waveshare RS485 to Ethernet adapter with RTU over TCP. The RS485 is connected to a ventilation system. When i try from Modbus Poll from my PC it works absolutely fine with reading and writing. When i add…
Stig
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Why is there an Error with modbus using TCP Matlab?

I'm working on a matlab project to remotely control a machine using the Modbus TCP protocol. The server is in "Listening" and the ports are open but when I try to read an address it doesn't work. Error of the type "a communication error occurred…
Mathis Sp
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How to use write_single_register function in pymodbustcp library

Using RTDS's MODBUS communication protocol, we intend to communicate with Python using the pyModbusTCP library. The register was assigned by mapping the components of the system modelled by RTDS as follows # RIR: Read Input Registers (16 bit word,…
joonbyeok Hwang
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Node-Red Bit to Word Node

Looking for a node that can join 16 bits into a word for writing over Modbus TCP. I am using the 16Bit Split node for reading each bit from a Modbus Flex Getter and wanted a similar functionality to be used with Modbus Flex Write. Attempted to make…
automationguy222
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ModbusTcpClient: How to read long integer values from Input registers in python

I am trying to get data from a sensor using ModbusTcpClient as below client = ModbusTcpClient('xx.xx.xx.xx', port=502) connection = client.connect() request = client.read_input_registers(220,2, unit=51, debug=False) result =…
SM079
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Modbus TCP and RTU in a single application

I have a Modbus-TCP stack and a C++ wrapper(application) on top of that stack... This C++ application is running smoothly. Now I want to go for Modbus-RTU capabilities as well. So my question is... Will RTU and TCP co-exist under a common C++…
Prasad Patil
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Auto discovery for Modbus TCP and RTU

I am new to Modbus protocol. I am working on a simple Modbus TCP application. In future I will jump to RTU as well. Currently I need to manually add the slave's IP address in the master and then I am able to communicate with that particular slave. I…
Prasad Patil
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modbus controller: Trying to get data from Modbus controller using IP address in Python

I am trying to get data from Modbus controller using IP address. from pymodbus.client.sync import ModbusTcpClient as ModbusClient client = ModbusClient("10.98.237.80", port=502, auto_open=True) client.connect() rr =…
SM079
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Extract desired information from an industrial pcap file in Python

I have an industrial pcap file that includes Modbus/Tcp protocol and an extra layer Modbus Protocol. Modbus/Tcp protocol includes: Modbus/TCP Transaction Identifier: 27763 Protocol Identifier: 0 Length: 6 Unit Identifier: 247 I am…
AHSAN YAZDANI
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Trouble Reading Modbus Data with Python Threading: Connection Issue with Modbus Slaves

I am using the Python threading module and Pymodbus library to read Modbus TCP data. import threading from pymodbus.client.sync import ModbusTcpClient import time import os,time,sqlite3 as sql class modbus_thread(threading.Thread): def…
ozan
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Values received over Modbus TCP are much higher than expected

I have some measurements coming in from over Modbus TCP/IP and I have successfully identified the values that I'm trying to measure. However the values all differ by some amount from the measurements. For example the voltage should be at 232 V, but…
Ale Pan
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Communication with two RaspberryPi over Modbus-tcp protocol

Here is code for communication over Modbus-tcp with txo Raspberrys: Master code: #include #include #include int main(int argc, char *argv[]) { modbus_t *ctx; uint16_t tab_reg[64]; int rc; …
Bozana Savkovic
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Accessing ethernet port connected to android phone

I am trying to build an app for modbus tcp/ip client on my android device. I've attached a USB to ethernet port converter and I'm trying to communicate through my laptop as a server. I'm not able to connect to the network with the error…
Darshan Modi
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How do I view raw memory addreses of MODBUS TCP/IP holding registers in CODESYS

For a work project, I have to read a bunch of holding registers from an IFM CR1203 PLC that is programmed using CODESYS 3.5. The PLC will be running a slave instance and the device reading the holding registers will be a PC running a custom…
Rikus Coetzee
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connectivity between Java web app and Robot programming Ur16e

I am trying this for the first time can you help me with this? I have developed an HMI using java(spring boot frame) can say a web app. I have programmed the cobot(UR16e)universal robot using ROBODK stimulation. (I programmed using Interface but its…
Mohammed Khadeer
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