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).
91 questions
1
vote
1
answer
119
views
Software serial and RS485
I have 2 Arduino Nano that will communicate in half duplex mode with transceiver using MAX485. But the master has libraries like Wire.h, uses tone() and also receives UART communication.
I'm a ...
- 113
-1
votes
1
answer
120
views
Connecting the device to Arduino via the UART protocol
The essence of the task
I have a task to connect an external device with my arduino and transfer data to each other via the UART protocol. The external device has 4 pins (Two for power supply and RS-...
- 1
0
votes
1
answer
133
views
Extra 0x00 sent with RS485 message
I am currently trying to use an arduino to send an RS485 via an SP3078EEN RS485 transciever. I have my arduino code set the DE pin high, wait 1ms, then write and flush a data buffer to the serial ...
0
votes
1
answer
327
views
RS485 message edit on the fly between EV charger and energy meter
I am trying to connect Feyree smart EV charger with Dynamic Load Balancing to DTSU666 smart meter via RS485.
Dynamic Load Balancing is a function of EV charger that lets you dynamically change charger ...
- 19
1
vote
0
answers
319
views
Is it possible to create a RS485 bridge over Wifi using 2 ESP07's
I've got a solar energy inverter that has a RS485 port for connecting a meter. You can place a separate energy meter in your distribution panel at home, that measures things like power usage, purchase ...
- 123
0
votes
2
answers
412
views
ArduinoModbus / RS485 conflict between Serial and Serial1
I am attempting implement ArduinoModbus on my STM32 Poternta H7 using the breakout board.
Its well documented that in ArduinoRS485 that the RS485 object is hardwired. If you are using the PH7/Breakout ...
- 33
0
votes
0
answers
999
views
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 ...
- 297
0
votes
0
answers
187
views
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 ...
- 9
2
votes
0
answers
380
views
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 ...
- 151
1
vote
2
answers
9k
views
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 ...
- 1,435
0
votes
0
answers
1k
views
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 ...
- 101
1
vote
0
answers
465
views
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: ...
- 173
2
votes
1
answer
4k
views
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 ...
- 21
6
votes
2
answers
5k
views
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 ...
- 133
1
vote
0
answers
280
views
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 ...
- 11