Questions tagged [modbus]
Modbus is a simple protocol for serial communication between electronic devices.
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Modbus rtu server library which logs the requests
Kindly seek help. In my project I want to ‘fake’ a smart meter via Modbus rtu server for a solis inverter.
Somehow the solis realizes that I am faking him, so I am wondering which Modbus rtu server ...
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Arduino RS485 do I need MAX485?
I'm trying to connect sesnor that use RS485 (I'm almost sure that's modbus). The sensor has RX/TX and +/- wires. Do I still need a component between the RX/TX pin from the Arduino UNO and the sensor ...
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Modbus RS485 Decode the message received
I'm try to read some value from a soil NPK sensor using RS485 Modbus e Arduino uno.
I menage to sent the request msg and I got the response but now i don't know how to read the response in order to ...
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Trying to use an Arduino Uno to control two slaves with one master but its not working
I am trying to use following code but its not working. Need a help in this regard.
#include <SimpleModbusMaster.h>
#define baudrate 115200
#define timeout 2000
#define polling 500
#define ...
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0
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Using ModbusRTU.h, what would cause holding registers all read 0?
I'm working with a 32-Input Modbus RTU module using RS485. I'm trying to read/poll the inputs to check for ON(1) states. I have tested this module with Arduino UNO, Radzio! Modbus Master simulator, ...
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Cannot read values stored in bool* pointer [closed]
I'm trying to read values stored in a bool* pointer from a modbus coil call.
I'm using modbus-esp8266 library. it's all ok with Input Registers and Holding Registers but i cannot read the result of a ...
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ESP8266 - MAX3485 Modbus not getting data
I'm trying to connect a modbus meter to a nodeMcu LoLin v3
I'm using a MAX3485 module to transfer the TTL to a RS485 connection.
The modbus server has unitId 1, baud rate 9600 and no Parity
This is ...
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Modbus rtu data decimal to float conversion
Hi,am trying to communicate with power-factor controller [Selec APFC 148-312] using modbus RTU,am following example sketch from modbusmaster library. am able to get the raw data from the instrument ...
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0
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ARDUİNO MODBUS TCP CONNECTİON
I am trying to communicate with PC by using modbus TCP communicate. When I use this code I can't communicate. Dou you know guys what is the problem? My ethernet Module is working I know that because I ...
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When it comes to UART to RS485 communication, what is the difference between the 'MAX485' and the 'HW-0519' module?
I recently found this model with the ID 'HW-0519' on it. It can be found online (HW-0519 in Aliexpress) and is sold for the purpose of converting UART to RS485 communication using Arduino devices. The ...
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Which sensor bus best to use?
I am working on a project which requires a dozen VL53l0X I2C-TOF sensors to be polled by one master MCU over a few meters of cable.
Thus, I decided to accompany each TOF by an Atmega8 acting as a ...
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Connect 12 V DC sensor to Arduino Uno using TTL RS485
I'm trying to connect an Arduino Uno with a BGT PM2510 sensor (which uses 7-12 V DC) by using a UART TTL to RS485 Two-way Converter.
The only thing I wonder about is: can the sensor damage the MCU?
...
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Simple ModBus Master function 15
I have a simple setup with arduino Nano as slave and a arduino Mega as master
Can anyone explain how the function 15
FORCE_MULTIPLE_COILS
Works
i have been running some test on this
and cant figure ...
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Modbus TCP together with MQTT over same ethernet
I'm currently in a planning phase for a project.
I want to read some sensor data over Modbus TCP, do some simple calculations on the Arduino and publish the results over MQTT. Which means I have 2 RJ-...
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Modbus TCP/IP using Arduino uno and ENC28J60 module
I have this project where I need a modbus tcp server that will host a series of sensor data for other modbus client devices to read. I use this Library by Andresoarmento
This is the code i am using ...
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The Pfieffer Vacuum Protocol for RS485
i am working on a control Interface for serveral Components including turbo Pumps from the company Pfeiffer.
The communication will be done according to the The Pfieffer Vacuum Protocol for RS485.
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ESP32-POE/ISO unstable after 10 days of power up
i have one ESP32-POE and ESP32-POE and i'm using the Olimex RS485 module to read a power meter that is placed near the ESP32 (5 meters of CAT5 cable - 9600 8N1).
My device has this workflow (it's ...
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2
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Arduino Modbus Slave Library Needed
We are building a circuit based on ATMega328* that :
Reads 32 current transducers, multiplexed into one Analog Input,
Reads 12 voltage transducers, multiplexed into one Analog Input,
Reads 6 ...
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ModbusMaster - Read 64 Bit integer
i'm using ModbusMaster library (Repo) to read from a device some registers.
Many of them are float and i've no problem to read them using the following code:
//for float conversation
union
{
...
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Modbus programming
I have a Controllino Mega running a code that rotates a stepper one revolution CW, and one revoluction CCW.
I need the program to run, just when a signal is received from an HMI that I have connected ...
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Controllino Mega and Fatek HMI
I have a setup that controls the rotation of two stepper motor using Arduino UNO, HBS860H stepper drivers, 4X4 keypad and LCD screen. I have replaced the Arduino Uno by a Controllino Mega and it works ...
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How can i read and write the data from a Delta plc-s series through Arduino UNO?
I am trying to communicate PLC with arduino through rs232 as well rs 485. But, I am not able to read and write data. I can observe the data in PLC through ladder logic but not in arduino. I am trying ...
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Controlling VFD with ModBus RTU via RS485 and Arduino
I am attempting to control a Folinn VFD (Manual: Manual) with an Arduino Uno via a MAX485 module such as this.
Pins for MAX485:
DI > D8
DE & RE > D10
RO > D11
VFD settings:
F00.01 set to 2
...
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can ModbusRtu.h library send data from slave to master using modbus(RS485) module?
i am using ModbusRtu.h library for modbus protocol. it works for sending data from master to slave but it can not send data from slave to master.
master code:
#include <ModbusRtu.h>
#define ...
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0
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I am interfacing Amonia Sensor RS485 output with Arduino Mega . not getting any response
I am interfacing Amonia Sensor RS485 output with Arduino Mega but not getting any response. i need to transmit {0x06, 0x03, 0x00, 0x00, 0x00, 0x04, 0x45, 0xBE};
frame to sensor then senor will send ...
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How to Use Function Code 6 Modbus RTU library
I'm trying to communicate with a temperature controller using Modbus RTU.
I used this Arduino library.
I was able to read PV(current temperature value) using below code. It uses Function code 4.
I ...
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Reading a simple sensor with Modbus RTU on Arduino Uno
I'm integrating a wind direction- and speed sensor with an Arduino. It communicates over RS485 Modbus RTU, which I don't have any experience with.
The documentation is very short, and it just says:
...
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NodeMCU Modbus interfacing with Pressure Multi-Switch
I've been trying to interface between a NodeMCU and a Dotech DPX200 Pressure Multi-Switch over Modbus RS485 using a MAX485 Module for the past few weeks, going through nearly every Modbus post on this ...
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Stack smashing protect failure ESP32 with Modbus RTU
I'm doing a project using an ESP32 TTGO with LoRa, the Max485 and a WELLPRO ADAM 8082 for Modbus communication. I'm trying to use the ESP32 as a master to and the ADAM as a slave.
I'm also using Node-...
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Arduino Mega with SIM800L running Modbus TCP/IP
I'm trying to set up an Arduino Mega with a SIM800L module and trying to get Modbus TCP running on said Mega. I've set Modbus TCP over wifi and serial before but I used libraries for those. The ...
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Unable to read data more than once via Modbus RTU
I'm a newbie to this forum so kindly excuse me for any errors.
I'm using an Arduino Uno and Max485 (RS-485 to TTL) to communicate with a Power meter, but I'm able to receive the data from the Power ...
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Arduino Uno & ESP32 communication using RS485
I am trying to establish a communication between Arduino Uno ( Master) and ESP32 (Slave) using RS485 protocol (using MAX485 module).
I have successfully done this between two Arduino Unos. ...
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RS485 Arduino Communication Issue
Friends, I am trying to achieve half duplex communication between two Arduinos using RS485 Protocol. The hardware I am using is a MAX485 module and an Arduino Uno. I am using the SoftwareSerial ...
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Cannot read modbus data repetitively
I try to communicate with 2 RS485 sensors (pH and EC), but I have some troubles with my code. First, I tried to get data from just one:
The function in charge of request sending:
String GET_probe(...
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Arduino as Modbus RS485 slave using only 2 Digital pins
I want to use RX(0) and TX(1) Pins to make Arduino as an RS485 slave. To do this I am using MAX485 IC (Breakout board) https://datasheets.maximintegrated.com/en/ds/MAX1487-MAX491.pdf
The problem here ...
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Arduino Modbus slave error
I am trying to use Arduino as Modbus- RTU slave and Raspberry Pi as a Modbus master I have interfaced Max485 (RS485 to TTL converter) with Arduino and Rs485 to USB converter in Raspberry Pi, Initially,...
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Arduino Modbus - Rtu slave with Raspberry pi using MAX-485
I am trying to use Arduino as Modbus- RTU slave and Raspberry Pi as a Modbus master
I have interfaced Max485 (RS485 to TTL converter) with Arduino and Rs485 to USB converter in Raspberry Pi, Initially,...
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Problem with modbus communication between two arduinos when writing more than 27 registers
I have the following problem:
I want send 200 registers from a modbus master to a slave. Both are arduinos.
I can't send more than 27 registers. When I send more i get the Errorcode 255 which means ...
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Modbus IP with Simply Modbus TCP
include SPI.h
include Ethernet.h
include Modbus.h
include ModbusIP.h
//Modbus Registers Offsets (0-9999)
const int SENSOR_IREG = 100;
//Used Pins
const int sensorPin = A0;
//ModbusIP object
ModbusIP ...
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Using Modbus-RTU with Arduino and temperature controller
I'm trying to connect with a 4 channel temperature controller using Arduino Modbus Library.
This is a part of my temperature controller datasheet. It has register for read PV of each channel.
I have ...
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Using Modbus TCP server on Arduino
I have a scd30 sensor wired to an Arduino Uno. The scd30 works on the I2C protocol. I am able to read data live on the serial monitor on the Arduino IDE. I have an ethernet shield on my Arduino. I ...
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Multiple #ifndef vs. single one #endif
My question is connected with the issue as linked:
Is there any good working MODBUS TCP master library available for Arduino?
An example of Modbus TCP master library as suggested in the post above. A ...
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Arduino Modbus RTU VFD control
I need help with this code:
/**
* Modbus master example 1:
* The purpose of this example is to query an array of data
* from an external Modbus slave device.
* The link media can be USB or RS232....
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How to make I2C work on RS485?
I'm trying to optimize the communication (minimize wires) on a project where I can control a motor and toggle some 230V devices by using RS485 and I2C.
On this project, I'm using an Arduino (Mega) ...
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1
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Arduino Modbus Master code to read data using arduino uno from EB meter
I am using DC energy meter as slave.When I am testing DC energy meter using Modbus tester tool,its showing value from 1 to 24 register.I am using my own atmega328P with on board RS485 as a master ...
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Modbus RTU controller monitoring with arduino and RS485 module
I'm a medium user in Arduino. I baught a pHmeter controller with RS485 output (MODBUS RTU protocol).
I want to get pH value read by the controller over RS485 module and Arduino.
According the ...
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Arduino ModBus RTU master communication with Power Meter problem
i have an arduino UNO with RS485 module.
I have made this connection:
And i have an problem with communication of this module with power meter
"InePro PRO-1Mod"
(datasheet) over ModBus protocol. I ...
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Cannot obtain reading from meter (Modbus)
I have a system in which I am taking readings from a meter and processing it through an Arduino Nano. My code looks as follows:
#include <SoftwareSerial.h>
#define SerialControl 7
#define ...
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957
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float not a float
I am trying to read a SDM220 meter on my solar setup. I've been reading it using Modbus SCADA, so know it all works ok.
But I want to read it with my Arduino Mega 256. My problem is that when I run ...
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Modbus RTU slave library
I want to use an Arduino Genuino Zero as a Modbus slave. I tried to search on google, and found a library. When I try using the library, I get a timeout error.
Can anyone tell me how to solve that ...
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