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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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Java Programing on Modbus TCP to Convert 4 Integer Registers to Double value

Using java programming and with the help of Modbusutill(Jmod) jar I developed a code that it will connect to PLC through Modbus TCP. Here I got the situation that I need to convert 4 input registers to double value. Say registers are…
Praveen reddy
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How can I send with 'struct.pack' type over Modbus TCP?

I want to send packet over Modbus TCP. I want to use: But I can not send this way how can I send this packet? (I don't know something will be) req = struct.pack( 'Something', transaction, identifier, length, unitid, func_code, reg_addr ) These…
CKocar
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Pymodbus read holding registers

I was assigned to perform the task without any documentation. I have a problem with reading data from MODBUS. This is the script that I was able to create: from pymodbus.constants import Endian from pymodbus.payload import BinaryPayloadDecoder from…
miesiu
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Creating async modbus server python problem

I am new to Python and trying to create a modbus server with pymodbus module. I follow tutorial on link, but when I run script I got an error: $ python2.7 server1.py INFO:pymodbus.server.async:Starting Modbus TCP Server on 192.168.1.100:502 …
Tilen Špacapan
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Modbus TCP master to multiple slave Connectivity

I am developing a windows form to function as a modbus tcp Master Simulator.I am using NModbus library. I want to connect to multiple slaves simultaneously and do the read and write operation,does the NModbus library supports this kind of…
Harshith R
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EasyModbus: disconnecting from network doesn't change the connection state

In a C# application I use EasyModbus to connect to a remote server: ModbusClient client = new ModbusClient() { IPAddress = "192.168.1.100", Port = 502, ConnectionTimeout = 200 } try { client.Connect(); } catch…
Mark
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Optimize Modbus requests

I have a QMap where the key is the address of Modbus register, and MyData is my own struct that contains some information not important for this question. The keys set might be quite large (say 2000 values) with some of them close each…
Mark
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How to overcome to "Address already in use" in ModbusTcpServer with restarting app?

Description and code: I'm using the Synchronous ModbusTcpServer with pymodbus library to create a Modbus Slave/Server, that here's the code: from pymodbus.server.sync import StartTcpServer, ModbusTcpServer from pymodbus.device import…
Benyamin Jafari
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How to check pymodbus version for decode a float_32 value?

I read and decode float_32 value using pymodbus. Before, I decode that with the following code as simple: from pymodbus.client.sync import ModbusTcpClient from pymodbus.constants import Endian from pymodbus.payload import…
Benyamin Jafari
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modbus rtu over tcp (modbus tcp gateway)

Is it possible to build a modbus-RTU ethernet gateway using a linux box or arduino? I have plc slaves linked together using modbus RTU, and I want to connect one of them over TCP with my pc as master. I wonder if I can use a linux box (rasbery…
ramiwi
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How to retrieve data size larger than Qt Modbus InputRegisters?

From what I understand, the range of QModbusDataUnit::InputRegisters is range 0-65535 which is unsigned short. The method to read 1 unit of inputregisters is as follows: QModbusDataUnit readUnit(QModbusDataUnit::InputRegisters, 40006, 1); The value…
user1157977
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Reading data on the Modbus network from the Altivar frequency converter or MODICON PLC

tell me whether it is possible to directly read the values ​​of the registers from the equipment using the Modbus protocol. I want to implement in java language reading registers and outputting them to the jsp page. The program is needed for the…
Миша Ивченко
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IOT continually connection to PHP through wifi and modbus

I am now working on PHP part. I know pretty less about IOT so the question might be strange, but I will be appreciate if anyone can give me an example, concept or even a way to learn. The idea way is to let the PLC device can keep connection with…
KJ_CHIU
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Modify "Modbus TCP" to "Modbus RTU" with QT - QModbusTcpClient

I would have to send Modbus request for specific data, my problem is that I have to use mobile communication, wifi, connect to a custom electronic card, which is right in Modbus RTU. My working code connecting to the electronic board: #include…
Mr. Developer
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MODBUS-tk Read floating point values from slave in the master

I have created modbus slave to write data to the registers. I am able to write both float values and integer values from the slave side. In the modbus master I am able to access only the integer values but not able to read float values. I went…
Abhinandan s
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