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The RS-485 standard is superseded by TIA-485, but often engineers and applications guides continue to use the RS designation.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

86 questions
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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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What Ohm Termination Resistor is needed for this schema ? What, Where and How?

I'm building a Master-Slave system using some arduino pro mini as slaves and a Mega 2560 as Master to communicate over RS485 config via MAX485. Since i'm newbie in RS485 i know that i need to put some termination resistor somewhere is the line but i…
Safa Seed
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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 some code but it returns an E2 error which means…
hrishi akash
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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 had to convert it to ASCII. But that wasn't the…
Huppel
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RS485: is "Y" multidrop allowed?

I imagine that the proper way to implement an RS485 multidrop bus is the following: What happens if, in order to save cables, I connect the same 5 nodes above using this other topology? Will it works? If no, why? If "maybe", under which…
Damiano Verzulli
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Standard Length Messages over RS-485

I am a bit confused. So I want to send messages between two arduinos over RS485, but these are not fixed length, naturally, I have to send the length of the message or add a delimiter to understand that my message has ended. Suppose, now I create a…
Rupin
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Problem using ICSC (by majenkotech) in RS485 bus

I want to communicate with an RS485 Bus consisting of 5 Arduino Pro Minis as slaves and one Arduino Mega 2560 as Master. I found a great library for this. According to the documentation provided by the author of library I can use: ICSC icsc(1, 9600,…
Safa Seed
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Interfacing Gammon's RS485 with computer

I'm using the non-blocking RS485 Gammon's library for Arduino (as shown at http://www.gammon.com.au/forum/?id=11428) to handle the communication between some arduinos. Now I'm having trouble to add a Raspberry Pi (or otherwise a non-arduino…
Salvo Passaro
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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 in this picture: The side that connects to the Arduino has four pins,…
user1584421
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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-arduino-pro-mini But now my problem is The master…
priya
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