EV3 WIFI connection problem - BrickFinder (discover)

This is where you talk about the EV3 software itself, installation issues, and programming talk.

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MarkoO
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EV3 WIFI connection problem - BrickFinder (discover)

Postby MarkoO » Fri Apr 21, 2017 11:35 am

Hi.

I got a tp-link wifi dongle and I succeeded in connecting it to my wifi router. On the other hand, my PC is also connected to the router. But once i run brickFinder discover method, there is no ev3 found. I dont know why. Do you have any clue? Also once I insert Bluetooth dongle into my PC i get an ev3 network to which my pc can connect. Thank you. Marko

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gloomyandy
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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby gloomyandy » Fri Apr 21, 2017 4:52 pm

I'm not sure what you mean when you say you get a Bluetooth network that your pc can connect. I assume you are having to connect to the PAN before this happens? Are you saying that once you have connected your PC to the PAN you are able to discover the EV3? Is your WiFi network working at all? Can you connect to the EV3 using the IP address displayed on the EV3 screen (over WiFi, not via the PAN)? What addresses are displayed on the EV3 screen?
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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby MarkoO » Fri Apr 21, 2017 5:18 pm

WiFi network works. I connected my EV3 to the WIFI network. On the EV3 I can see two ip addresses, one of the EV3 and one of the WiFi network. I succeeded in sending a simple program to specific EV3 from PC using USB (wired connection). But once I use only the WiFi network, I can not do the same. When I try that (having pc and ev3 connected to the router) i get the following: "java.rmi.ConnectException: Connection refused to host: 10.0.1.1; nested exception is: java.net.ConnectException: Connection timed out (Connection timed out) Caused by java.net.ConnectException: Connection timed out (Connection timed out)".

The thing that I mentioned regarding Bluetooth connection is that once I enable the Bluetooth on my PC, and ev3 is connected to the WiFi network (PC as well ofc), I can see a new WiFi network called "EV3 Network" and once I click on it, it connects me to that network.

So I just want to use the wifi network to talk to the ev3 (no PAN). The only thing that I did is that i connected the ev3 to the wifi router. After that I could not locate any ev3, "No EV3 found".

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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby gloomyandy » Fri Apr 21, 2017 6:48 pm

You can't use the 10.0.1.1 address over WiFi, you need to use the other address shown on the EV3. Are you sure you have not set an explicit address for the EV3 in the eclipse plugin settings. When you attach a WiFi dongle to the EV3 it will have two network addresses one will be 10.0.1.1 and is used for USB and Bluetooth/PAN connections. The other is the address of the EV3 on your WiFi network.

I have no idea what you mean by you can see a new WiFi network when you have Bluetooth setup. That does not make a lot of sense. The only sort of network that is supported over Bluetooth is a PAN it is wireless but not in the same way that WiFi is. What is the operating system of your PC? On Windows WiFi and Bluetooth networks typically show up in difefrent places and it is obvious what they are.

You still have not said if you can actually talk to your EV3 over WiFi. Can you ping the address shown on the EV3 (not 10.0.1.1)? If you can then you should be able to connect to that address by using it explicitly. Set it in the eclipse plugin settings https://sourceforge.net/p/lejos/wiki/In ... %20plugin/
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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby MarkoO » Fri Apr 21, 2017 7:07 pm

I can ping the second address shown on the ev3 (Not the 10.0.1.1). But if I put that address explicitly and set it up in eclipse, then it would be able to discover only that specific ev3, right? I want to discover all available ev3s. I left my pc, i will have it again tomorrow morning and i will try it, but will the discover() method find only that ev3?

I am using ubuntu 16.04.

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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby gloomyandy » Fri Apr 21, 2017 7:31 pm

I think first of all you need to actually establish that you can use your WiFi setup, so put the address into your eclipse settings and make sure you can upload a program. Once that is working you can worry about multiple devices. But even then I'm not sure how you are going to work with eclipse with them. If you done' specify a particular EV3 how do you intend to control which EV3 will get a downloaded program? The discover method will return multiple EV3s but the eclipse plugin simply uses the first one in the list.

So what makes you think that discovery is not working? What settings do you currently have in the eclipse plugin?
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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby MarkoO » Fri Apr 21, 2017 7:37 pm

Ok, i understood the way how to send the program. I have to specify the ip address.

But, When I run the ev3control center, and I click search, i get a popup "no ev3 found". That is my main concern. Sorry for misunderstanding :)

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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby gloomyandy » Fri Apr 21, 2017 7:42 pm

Yes but you have still not said if you can actually talk to the EV3 over WiFi, can you actually connect to it if you specify the IP address? If you can then we need to understand why the discovery is not working, but if you can't then you may have other problems.
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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby MarkoO » Fri Apr 21, 2017 7:45 pm

Ok. I will be next to the PC tomorrow morning again and I will do it immediately and let you know. Thanks a lot for all the replies :)

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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby MarkoO » Sat Apr 22, 2017 6:19 am

Ok, Hi again. I have tried to send the program from PC to EV3 by specifying the ip address in the eclipse settings, as we said, and it works perfectly. Also I have just tried to open the socket with specific ip address of a robot and port and succeeded in sending the message to the robot (robot was waiting for the PC to connect - ServerSocket serv = new ServerSocket(1235); Socket s = serv.accept(); - ).

On the other hand, when I go to the ev3 control center and "search", i get nothing (no ev3 found).

Also, if I run just the following code - BrickInfo[] bricks = BrickFinder.discover(); for(BrickInfo info: bricks) { System.out.println("loop");} - on the PC, I do not get anything.

So, ev3 control center and method BrickFinder.discover() do not regognize EV3s, while I can send the program to the specific EV3 and ping its address as well.

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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby gloomyandy » Sat Apr 22, 2017 6:51 am

What version of leJOS do you have installed, is it the same on the EV3 and on your PC? You really need to be running 0.9.1 on both to have a good chance of having discovery work.

Do you have a firewall like UFW running on your Ubuntu system? What happens if you turn it off?

Are you using WiFi or a Wired connection between your PC and your router?

Are both your PC and your EV3 connected to the same sub-net?

I've just tried discovery to an EV3 here from 3 different systems including Ubuntu running a virtual box VM, works fine for me on all three.
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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby MarkoO » Sat Apr 22, 2017 7:49 am

Ok, so, firewall is disabled, my pc has wireless connection with the router and they are on the same subnet. But the version on EV3 is 0.9.0 so that is maybe a problem.

I got this SD Card with lejos 0.9.0 from a professor, do you have any good tutorials that can show me how to change the lejos on that SD card? thanks :)

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gloomyandy
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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby gloomyandy » Sat Apr 22, 2017 3:58 pm

0.9.0 uses a different mechanism to locate an EV3 and it was reworked for 0.9.1 to make it more reliable. So I would highly recommend that you have that version on your PC and your EV3. The wiki gives some details of how to install leJOS:
https://sourceforge.net/p/lejos/wiki/In ... g%20leJOS/
The following is a step by step guide for Windows:
https://sourceforge.net/p/lejos/wiki/Wi ... tallation/
Maybe you should talk to your professor about this before you change things, they may also be able to help you with the install.
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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby MarkoO » Tue Apr 25, 2017 8:14 am

Hi Andy. I succeeded in changing the EV3 version into LeJos 0.9.1. I used the following link since I am using Ubuntu: https://sourceforge.net/p/lejos/wiki/Cr ... SD%20card/

It was pretty straightforward and now when I run the discover() method I can see the EV3. Thanks a lot for all the advice. Marko

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Re: EV3 WIFI connection problem - BrickFinder (discover)

Postby gloomyandy » Tue Apr 25, 2017 10:04 am

Glad to hear you have things working. Be sure to pop back and tell us more about your project when you have it finished!
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