Problems Arduino Nano V3 and MAX485 no clear connection

Control Boards, Controllers, Tethers, Ect.
Matt87
Posts: 12
Joined: Jun 9th, 2020, 12:18 pm

Problems Arduino Nano V3 and MAX485 no clear connection

Post by Matt87 »

Hey folks, I'm working right now on a prototyp für a RS485 connection betwen two Arduino Nanos.
If the result good and it will working fine i will do the next steps to build the ROV.

I have many issues on my Connection. I want to use the programming parts from this code togehther with the MAX485 driver:
http://www.techmonkeybusiness.com/rov-c ... ition.html

So until now i using the <SoftwareSerial.h> and the <EasyTransfer.h> Library.
I managed to control a LED on both Arduino. But to control a Servo I have many problems.
The Servo did not reach the right position from the input Poti of the other arduino.
The Servo is just wobbeling or the LED works only one time.
Baudrate is 9600. I use pin 10 for SSerialRX and pin 11 for SSerialTX.

My first question is, is it possible to use the <Easy Transfer.h> Library and a MAX485 together or should I use a other Library?
Is there an Example from a ROV with the MAX485 communicaton driver? :idea:

Thanks

Thanks
asesorplaza1
Posts: 187
Joined: Mar 4th, 2018, 6:11 pm
Location: Valverde de Júcar, Cuenca, España

Re: Problems Arduino Nano V3 and MAX485 no clear connection

Post by asesorplaza1 »

Buenas noches.

Bien venido al club de los que tenemos problemas de estabilidad de comunicación entre Arduinos, yo también empecé con TechMonkey, y ampliado bastante el código. Pero llega el momento que introducir cualquier cambio en el código, desestabiliza la comunicación, por lo menos esa es la conclusión a la que he llegado yo. Estoy utilizando 2 Arduino Mega 2560, y también tengo problemas de comunicación.
Hay un compañero en el foro que ya está usando ese tipo de controlador, para el apoyo de la conexión entre Arduinos, y yo estoy esperando que me lleguen para comprobar si consigo estabilizar la comunicación entre dos Arduino Mega 2560.
Te pongo los enlaces a los proyectos, que tengas suerte, y mantennos informados.

viewtopic.php?f=18&t=530

viewtopic.php?f=18&t=1908

Un saludo.


Good night.

Well come to the club of which we have communication stability problems between Arduinos, I also started with TechMonkey, and expanded the code quite. But the time comes for any change to the code to destabilize communication, at least that is the conclusion that I have reached. I'm using 2 Arduino Mega 2560, and I also have communication problems.
There is a colleague in the forum who is already using that type of controller, for the support of the connection between Arduinos, and I am waiting for them to reach me to check if I can stabilize the communication between two Arduino Mega 2560.
I put you the links to the projects, that you are lucky, and keep us informed.

viewtopic.php?f=18&t=530

viewtopic.php?f=18&t=1908

Greetings.
fryslan76
Posts: 290
Joined: Dec 18th, 2012, 4:52 pm
Location: Netherlands

Re: Problems Arduino Nano V3 and MAX485 no clear connection

Post by fryslan76 »

Is your issue simulair like this one: https://forums.adafruit.com/viewtopic.p ... 35#p339477 there are several solutions in that thread. I find the adafruit forum excellent fir debuging sensor issues.
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PhilA
Posts: 42
Joined: Oct 1st, 2017, 12:53 am
Location: Australia

Re: Problems Arduino Nano V3 and MAX485 no clear connection

Post by PhilA »

I have used the Techmonkey business code between two nano's with approx 90m of cat6 tether. I used the RS 485 set up and control functions between the nanos work fine. With my project though I couldn't get my I2c compass and depth sensor to work in the final setup, they originally worked then something went wrong so I left them off my project.


viewtopic.php?f=15&t=1968
viewtopic.php?f=18&t=1959
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Lucas
Posts: 33
Joined: Oct 2nd, 2012, 10:19 am
Location: MN

Re: Problems Arduino Nano V3 and MAX485 no clear connection

Post by Lucas »

Not exactly what you are looking for but some additional context. The EasyTransfer library has a fair amount of overhead. To decrease latency, I had my best luck by paring down and limiting what controls and sensors were sent across the connection.
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MarcoMota
Posts: 52
Joined: Jun 9th, 2020, 4:05 pm

Re: Problems Arduino Nano V3 and MAX485 no clear connection

Post by MarcoMota »

Why dont you use the UART serial comunication already implemented in arduino?

You can use seial.write and serial.read comands to comunicate between two arduinos. Of course if you want a really fast and relliable transmission you will have to think in using syncronous comunication and not asyncronous as you are using now.

You could maybe use SPI wich in theory it can be pretty fast (I have never used it in arduino).

Hope it was helpfull. <><
Matt87
Posts: 12
Joined: Jun 9th, 2020, 12:18 pm

Re: Problems Arduino Nano V3 and MAX485 no clear connection

Post by Matt87 »

PhilA wrote:I have used the Techmonkey business code between two nano's with approx 90m of cat6 tether. I used the RS 485 set up and control functions between the nanos work fine. With my project though I couldn't get my I2c compass and depth sensor to work in the final setup, they originally worked then something went wrong so I left them off my project.


viewtopic.php?f=15&t=1968
viewtopic.php?f=18&t=1959
Thank you for the advice. I tried already several codes. Nothing works good. The Servo for example moving just out of control back an forward. I control the servo by analog Input from the master. If i change the value the Servo seems to follow the input.
So about your link, thank you for that but there is no code on the link. :-( How looks your code now?

I uplode a scheme from my test wiring. I dont use Resistors and the Cable lentght is just 5 cm for testing.
Did I made anything wrong on the wiring?
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asesorplaza1
Posts: 187
Joined: Mar 4th, 2018, 6:11 pm
Location: Valverde de Júcar, Cuenca, España

Re: Problems Arduino Nano V3 and MAX485 no clear connection

Post by asesorplaza1 »

Buenas tardes
Aquí tienes algo que te puede ayudar bastante con la conexión de los módulos RS485, las paginas están escritas en Español, pero con el San Google Chrome las puedes traducir, un saludo.

Good afternoon
Here's something that can help you a lot with the connection of the RS485 modules, the pages are written in Spanish, but with the San Google Chrome you can translate them, a greeting.

https://proyectoarduino.com/comunicaciones-con-rs485/
Matt87
Posts: 12
Joined: Jun 9th, 2020, 12:18 pm

Re: Problems Arduino Nano V3 and MAX485 no clear connection

Post by Matt87 »

asesorplaza1 wrote:Buenas tardes
Aquí tienes algo que te puede ayudar bastante con la conexión de los módulos RS485, las paginas están escritas en Español, pero con el San Google Chrome las puedes traducir, un saludo.

Good afternoon
Here's something that can help you a lot with the connection of the RS485 modules, the pages are written in Spanish, but with the San Google Chrome you can translate them, a greeting.

https://proyectoarduino.com/comunicaciones-con-rs485/
Thanks for the link. :D
My Half Duplex Wiring is exactly like in the link.
However, there is one think what makes me crazy. If I connect Arduino with my Computer and open the Serial Monitor. The Connection works Fine.
As son I remove the USB I have the same issue.
Matt87
Posts: 12
Joined: Jun 9th, 2020, 12:18 pm

Re: Problems Arduino Nano V3 and MAX485 no clear connection

Post by Matt87 »

I also try this example out
https://naylampmechatronics.com/blog/37 ... duino.html
And it works fine. Servo is driving exactly the analog input of the master.
I'm not sure what example I have to use for the thusters.
I see here many examples.
The http://www.techmonkeybusiness.com/rov-c ... ition.html sems to be the best, but he doesnt use the MAX485 and I would like to have a stable connection arround 100 meters. :o
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