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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).

Digital communications networks implementing the EIA-485 standard can be used effectively over long distances and in electrically noisy environments. Multiple receivers may be connected to such a network in a linear, multi-drop configuration. These characteristics make such networks useful in industrial environments and similar applications.

The EIA once labeled all its standards with the prefix "RS" (Recommended Standard), but the EIA-TIA officially replaced "RS" with "EIA/TIA" to help identify the origin of its standards. The EIA has officially disbanded and the standard is now maintained by the TIA.

The RS-485 standard is superseded by TIA-485, but often engineers and applications guides continue to use the RS designation.

Source: Wikipedia

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How to interconnect multiple Arduinos with a Rpi to control home-lights/switches

While planning the lightning infrastructure (wall-switches and lights) of my new home (it's still under-construction) I choosed to go through the "automated route" way and due to my background (I'm an "old" system/network administrator with…
Damiano Verzulli
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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 MAX485 module (MAX485 in Banggood) is the more…
C Vith
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Modbus Communication protocol for Arduino as Slave

I have an Arduino Uno board, with these components: rs-485 Modbus module shield Multiprotocol radio shield board for Arduino In addition I have a level sensor which reads either 1 when it is above water, and 0 when it is below. I need to be able…
lshas
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How to solve Atmega 16A Serial write (println) hang with Arduino Uno firmware?

For doing some experiments I bootloaded an Atmega16a with Arduino Uno. I am powering my Atmega16a from Arduino UNO. I am not using any external clock. Atmega16a is connected to a breadboard. For bootloading I refer the site…
Sony Arouje
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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 controller's manufacturer, we should operate as…
Teddol
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Arduino network with minimum wiring

For a parking management system I am going to create an Arduino network. An Arduino with an ultrasonic sensor will be placed above each parking space. If car is parked at specific location Arduino will inform master (PC) and also turn RED light…
umair
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RS485 Multimaster Communication with collision avoidance

I'd like to know if there is an easy way to implement communication between multiple arduinos that avoids collisions using the RS485 module. My setup would have multiple masters that send messages to only one slave that performs a task upon been…
Max Rasguido
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Arduino throwing error while using modbus RS485 code

I have been trying to make a communication with my industrial drive. All I want to do is read a few values of drive, like current, voltage etc. For that I am using a library: I don't understand why it's happening. When the same code I have used…
user16682
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Pelco D Library for Arduino

Does anyone know of any Pelco D libraries available for Arduino? I already have a PTZ joystick controlling 3 PTZ cameras, but I would like to add an Arduino 'intelligent' controller capable of sending automated sequences of Pelco D commands…
Electroguard
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Long Distance Communication with Arduino

I am reading the value of six potentiometers with a TX Arduino and receiving that data and applying those numbers to a motor using serial. It is working fine through TTL but I am going to need to do this over a 60 ft tether. I have done a little…
mpgiii
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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 get the information I need. the following code sent…
Damiano Miazzi
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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 but data structure seems to be in decimal…
Ragaven N
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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? According to the information on the 12 V sensor, it…
Redplane
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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 problem. But when using the rs485 module, the…
Mohammad Bitar
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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 multiple boards without slave ID slave boards will send…
kobi89
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