Questions tagged [rs485]
also known as ANSI/TIA/EIA-485, TIA/EIA-485, EIA-485 or RS-485, is a standard defining the electrical characteristics of drivers and receivers for use in balanced digital multipoint systems. The standard is published by the Telecommunications Industry Association/Electronic Industries Alliance (TIA/EIA).
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ESP32 S3 Same code works on Serial1 but NOT on Serial0 for RS485 module
I have designed a test board to understand ESP32-S3 working pins. I am using USB interface D+, D- for programing so Serial0 is free to use.
This is my test circuit for testing an RS485 converter. For ...
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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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How can I control the assignment of DMX512 universes to WS2812B physical outputs sequentially
Background
I am using an ESP32 that receives sACN/DMX512 universes from a controller and am outputting those control signals to a strip of WS2812B pixels using Adafruit's library for WS2812B and ...
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Differences between two common RS485 to TTL modules
I want to "translate" existing code, that utilizes one of these modules, for the other module.
Specifically, i have code that utilizes an "RS485 to TTL converter". As you can see ...
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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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Why do I read my own transferred data during my RS485 serial comms?
I am writing a RS485 serial communication firmware for the ESP32 (the minimal code is at the end of the question you can paste it as an Arduino INO or in platformIO main.cpp file).
It is quite simple: ...
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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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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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Arduino modbus program error
I was trying to extract data from a multi-function meter with RS485 connectivity and I am using Arduino as master, Arduino Uno and multi-function meter are connected via MAX485 module.
I have tried ...
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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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RS-485 Serial communication problem with arduino
I use 485 modules to transmit data serially from one arduino uno to another uno.
If I connect the 2 arduino boards directly without using the rs485 module, the data is sent and received without a ...
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Read Internal Registers of RS485
I am trying to interface sele EM2M, I am using Arduino Mega with RS 485 module. I want to read the internal registers I am using ModbusMaster library. The data which I want to receive is in the ...
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Building RS485 serial to USB adapter with digispark
Is it possible to build an serial-adapter with digispark board?
Like: Embedded System with 2-wire RS-485 Port connect to my digispark board. Digispark Board is connected via USB to my Computer (...
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How to count number of bytes appearing in the Arduino serial?
I need to count the number of bytes appearing in the serial (UART bus) bus, how to count bytes in Arduino with Arduino Serial functions? is this possible?
Application -
RS485 communication with ...
kobi89
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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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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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Arduino RS485 communication protocol - minimising overheads and best practice
I'm building a single master multiple slave RS485 network for remote sensors on test equipment. I have the hardware built and working, and I can do a Serial.print on the master and have the slaves ...
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NodeMcu Communication to RS485 Device using TTL to RS485 converter
Good day everyone,
I am facing a problem when trying to use nodemcu (Nodemcu ESP8266 Lolin V3) to communicate with an RS485 device. I sent an enquiry ...
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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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Unreliable communication with low baudrate on Leonardo
I am using an Arduino Leonardo (more precisely this product), to communicate with servo-motors) using RS485.
Everything works fine as long as I don't go below a baud rate or 115200bps. If I go below, ...
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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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ESP32 Hardware Serial Flow control and full espressif/arduino-esp32 support
I have a similar issue. I want to use the ESP32 with RS485.
I have used the Arduino and this works well assigning pins, but it seems not to allow full use of the UART.
I see the new uarts in the ...
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RS485 communication problem
I'm trying to achieve RS485 communication between Arduino Mega and Arduino UNO as specified in following link:
https://www.engineersgarage.com/arduino/rs485-communication-between-arduino-mega-and-...
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Serial Module Echoing a `0x00`
I am having a problem with a MAXIM Serial module (Config A) with a simple repeating code from COM port. When sending a character (k:0x6b) I receive a (0x00) echo.
Without the module and just ...
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Arduino UNO and RS485 Communication Problem
I am learning Arduino, a beginner in programming. I want to use Arduino UNO to connect a wind direction sensor RS485. The problem is the output in the serial monitor, the return data from the wind ...
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NodeMCU: Wiegand not working for one device, while working for another
I'm using a NodeMCU, and a working code for reading Wiegand data, with this library.
I managed to successfully read the Wiegand signal from this device.
However, I also have this new AR-721H device, ...
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one Arduino with RS485 and Ethernet shields: does this work?
I'm planning to wire a few Arduinos together via RS485, and have one of them act as a hub that collects information from the others and presents it via http on an Ethernet connection.
For instance ...
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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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Serial Enable Maxim RS485 Pin
If I want to use a MAXIM 485 for a RS485 communication, is there any option to include the Control DE and RE' pin in a natural manner in the code, instead changing the control pin everytime I made a ...
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Arduino RS485 shield to RS485 temperature & humidity sensor
I’m try to get data from rs485 is not work please advise to me.
1. Try to connect PC usb485 to DY-MD02 is work.
Send command “AUTO” or “READ”
2. Try to Arduino rs485 shield to DY-MD02 is not ...
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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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Connecting multiple RS485 together
I am trying to build communication across multiple Arduino using RS485. When i am trying to connect 3 Arudino nano together using breadboard my code doesn't reach slave where as if i just if i do ...
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Arduino Hardware serial pins with RS485
I tried asking a question in my earlier post - SerialEvent with RS485 communication it helped me understand Hardware serial and Software serial but i had few more questions for which i started this ...
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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 Serial Communication not working with Arduino
I am trying to control 2 devices with my arduino using RS485 communication.
Basically switch on device 1 for 5 seconds when I send 'g' to the master. And switch on device 2 for e3 seconds when I send ...
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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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Electric meter with Arduino and RS485 module
I'm a Arduino newbie. I have an Electric meter with an RS485 output. I want to get the MeterID value over the RS485 module and the Arduino. I just have document from manufacturer.
Sent by computer : ...
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Arduino master/slave communication using RS485
I am using Arduino Uno as a Master Device and 3 Arduino Unos as slave devices.
I am sending data from each slave to master after every 3 seconds continuously, and is going to execute further logic ...
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RS485 Wrong Results in Serial Monitor(Controllino) - Right Results with Logic Analyzer
After searching the internet and trying different examples, I always get the same wrong response in the serial monitor.
Picture 1 shows the wrong results. At first i thought it was decimal and I just ...
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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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sending data with rs485
I need to read acceleration data with ADXL335 using ARDUINO MICRO (or NANO) and send this data with RS485 module to another RS485 module connected to an ARDUINO UNO (300m between RS485 modules). ...
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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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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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