Problems Arduino Nano V3 and MAX485 no clear connection

[asesorplaza1]

Buenas tardes
Yo también tengo esos problemas, los códigos de TechMonkey, solo sirven para los sensores que utiliza en su código, en el momento que se realiza cualquier cambio, el programa ya no funciona igual, y el Arduino, parece que se vuelve loco, y no te hace caso a nada de lo que le mandes desde el programa, por muchas líneas que modifiques.
Por lo que yo estoy viendo, te pasa lo mismo que a mí, que tu no encuentras un ejemplo en el que alguien explique cómo utilizar el RS485 entre dos Arduinos para leer y enviar los datos de varios sensores, solo encuentras como comunicar dos o más Arduinos con un solo sensor. Te pongo otro enlace donde el creador de la librería para el RS485 explica cómo usarlo, espero que te sirva de ayuda, un saludo.

Good afternoon
I also have those problems, TechMonkey codes, only serve for the sensors that it uses in its code, at the time any changes are made, the program no longer works the same, and the Arduino, seems to go crazy, and does not listen to anything you send from the program, for many lines that you modify.
From what I'm seeing, it happens to you the same thing as me, that you can't find an example in which someone explains how to use the RS485 between two Arduinos to read and send data from various sensors, you only find how to communicate two or more Arduinos with a single sensor. I put another link where the creator of the library for the RS485 explains how to use it, I hope it will help you, a greeting.

https://www.gammon.com.au/forum/?id=11428

[bigbadbob]

Hi!
I use techmonkey based code modified for my own needs, easy transfer protocol, and RS485 boards that don't need control lines for the tx/rx switching. I had no end of problems with the cheap rs485 boards and went for slightly more expensive boards that detect when you TX and do the switching for you. I've not had any rs485 problems since changing to the better boards.

[Matt87]

Hi!
I use techmonkey based code modified for my own needs, easy transfer protocol, and RS485 boards that don't need control lines for the tx/rx switching. I had no end of problems with the cheap rs485 boards and went for slightly more expensive boards that detect when you TX and do the switching for you. I've not had any rs485 problems since changing to the better boards.

Wich RS485 Boards are you using now?

[Matt87]

I have maybe stupid question. I using the MAX485 Bords and I power those boards and both arduinos with a seperate power source.
So the only connection between the two systems is the wires A and B.
Is it necessary to connect the GND together. GND from arduino Master to GND Arduino Slafe?
http://www.techmonkeybusiness.com/rov-c ... ition.html
Techmonkey connect Master an Slave over one GND wire. I think I have to do the same?

[asesorplaza1]

Buenas tardes.
La respuesta es SI, debes unir las masas o GND de todo el circuito.
Un saludo.

Good afternoon.
The answer is YES, you must join the masses or GND of the entire circuit.
Greetings.

[Matt87]

Buenas tardes.
La respuesta es SI, debes unir las masas o GND de todo el circuito.
Un saludo.

Good afternoon.
The answer is YES, you must join the masses or GND of the entire circuit.
Greetings.

Good afternoon
Ok, Thank you

[Bennachie]

Buenas tardes.
La respuesta es SI, debes unir las masas o GND de todo el circuito.
Un saludo.

Good afternoon.
The answer is YES, you must join the masses or GND of the entire circuit.
Greetings.

No, this is incorrect. With RS485 you do not need to connect the grounds between the two modules, especially if the distance between the modules is short (<1km). Under certain circumstances you can end up with a high potential difference across both ends and then you need the ground, but normally just the twisted pair is all that is required.

[bigbadbob]

sorry for the late reply.
these are the ones that gave me endless problems-



and these are the good ones-

[Matt87]

Thank you.
I'm almost done with my Rover Projekt.
The Full Duplex Communication working good. Only the Live View is a little bit noise.