Problem with Arduino Yùn at start [SOLVED]

Good morning everybody, I'm new of the Forum.

Two days ago, I got a new Arduino Yùn( I have already Arduino Uno and the Ethernet Shield). I'm in a trouble. I connected the micro-USB cable to Yùn and to computer(ASUS S300C with Windows 8.1) and I expected Yùn to act as an Access Point, but in the Available Wireless Networks in the PC it doesn't appear.

I installed Bonjour service and I opened 5353 port in the firewall(incoming and outcoming).

The PC wireless adapter is Qualcomm Atheros AR9485WB-EG.

So, I tried to connect the Ethernet cable to Yùn and to router(TP-LINK TD-W8951 ND), but the WAN LED remained switched off.

I tried to upload the sketch "Blink" and the led blinked.

To solve the problem of Internet, I tried finally to reset the board.I resetted all the 3 buttons ( the WLAN button for 5 seconds and then for 30 seconds) but the access point didn't appear in the PC.

Do I have to change PC settings?

Thanking you in advance for any help

Welcome! I'm sorry to hear you're having trouble.

First off, the LED's probably don't mean what you think they mean, at least some of them don't really mean what you'd think by looking at the labels. For example, the white USE LED has nothing to do with USB, it's an indication that the Linux side is fully booted up. I haven't really figured out the WAN LED, and I've not been able to correlate it to Ethernet status.

Be aware that it takes some time for the Linux portion to boot up: over a minute. That's a long time when you are waiting for a network to show up, which of course won't be available until,after the system finishes booting. Wait for the white LED to come on bright and steady, and then wait at least another 15 seconds after that for the network to appear.

Also, the long or short presses of the WLAN RST button won't be detected until the system is fully booted up, this is different from many other systems where yup press and hold the system restore button while powering on or shortly after power on. You must wait for the system to fully boot up before pressing the button. I see the blue LED flash rapidly when it's detected the start of a button press. If successful, the reset process could take many minutes to complete.

You could get the blink sketch working, so at least that part is good. Load the Yun Serial Terminal Example, start the Serial Monitor, then press the YUN RST button that's near the LEDs. You will be able to see the Linux boot up messages. If you wait for the system to fully boot (or at least not put out any messages for at least 30 seconds) and then copy and post the output, we may be able to tell if anything is going wrong.

If it does fully boot (white LED on bright) then click Send on the Serial Monitor and you should get a sign- on banner. Then you can type ifconfig in the command entry box and click send. That will tell you the network status, including Ethernet IP address, if it's connected.

Thank you very much for the reply!

From the beginning, the White LED has always been bright, together with the green power LED. When I connect Yùn to PC, there's a rapid flash of the RX led.

The blue LED has never flashed when I tried to reset the board.

I've uploaded YunSerialTerminal example(RX,TX and L13 leds flashed on) and I've opened the Serial Monitor.Then I pushed down YUN RST button, but nothing appeared.

I tried to click SEND, but nothing happened(except for a red little message in the window asking me if I wanted to end a line).

How much time I have to keep the YUN RST button pushed down?

Thank you in advance

muscedra: From the beginning, the White LED has always been bright, together with the green power LED.

Just to be clear: when you say "from the beginning" do you mean as soon as you plug it in and give it power (which would be a problem)? Or has it always come on after a minute since you've started using it?

I tried to click SEND, but nothing happened(except for a red little message in the window asking me if I wanted to end a line).

I don't think I've ever seen that message, I don't know what it is...

How much time I have to keep the YUN RST button pushed down?

Just for a moment. It's a standard processor reset button.

One quirk shared with the Leonardo is that the Yun actually shows up as two different serial ports: the normal port, and the bootloader. When you first plug in the Yun, it shows up as one port, then when you load a sketch the processor resets, the normal port goes away and the bootloader port appears. When done loading, the processor resets again, the bootloader port goes away and the normal port appears. On my computer, the Arduino IDE seems to get confused by this: I can select COM91 (the normal port) on the Port menu, then when loading code it switches to COM92 to talk to the bootloader. When it's done, the IDE is still stuck on COM92, and I have to manually switch it back to COM91 after my computer recognizes the port again. Maybe something like this is happening to you and that's why you don't see any output?

Another idea: Start with the YunSerialTerminal sketch loaded, and the board completely turned off and unplugged. Then plug in the microUSB connector to your computer (the board will power up and start booting) and then open the serial monitor (you may have to wait a few seconds for your computer to recognize the USB serial port.) You should see messages streaming by as the Linux side boots. Be aware that there are sometimes long pauses in the output, this is normal. The lines start with a time stamp in seconds, in square brackets - the last messages are typically in the 45 second range, but it still takes some time after that to finish booting.

Hi

When I said "from the beginning" I meant from the first time I plugged Yùn into computer, I've seen two LEDS ON:green LED and white LED. But the WiFi Access Point doesn't appear in the list of available wireless networks of the PC

When I upload a sketch, I have initially Yùn into COM7 port and it remains at that port also after the upload.

(by the way, I changed in the sketch the symbol TILDE with the sign'-',in order to try to change the speed of the UART- I don't have the symbol TILDE- and it worked: if I send '-1' it answer 'Speed set to 115200' or if I type '--' it answer 'Sending bridge's shutdown command')

I tried to connect Yùn after having it unplugged and then open the Serial Monitor, but nothing appears

If I send the command for the bridge shutdown, what should I see?

Thank you

muscedra: by the way, I changed in the sketch the symbol TILDE with the sign'-',in order to try to change the speed of the UART- I don't have the symbol TILDE- and it worked: if I send '-1' it answer 'Speed set to 115200' or if I type '--' it answer 'Sending bridge's shutdown command')

You may want to rethink that. The idea is that it is not a character that is normally used when talking to Linux, so that it can act as an escape character to talk to the code in the sketch. Normally, anything you send to the sketch via the USB serial port is passed through to Linux. Sending this character means that the next character should be processed by the sketch.

You can still use '-' as your escape character, but that means that any time you want to send '-' to Linux (which is often used for command line parameters) you will need to send '--' instead. Some Linux command line switches use '--' so you will have to double both of them and send '----'.

It's good that you are able to send the change serial port speed commands, as that shows the sketch is working and the computer to AVR processor communications are working. That command changes the speed of the communications between the AVR processor and the Linux system. The Linux side is always using 250000 baud (unless you've changed it, and given that you haven't been able to log in yet, it's safe to assume it hasn't been changed.) So, either don't try to change the speed, or only use the '2' speed option. If you tried changing the speed, perhaps to 115200 to match the Serial Monitor setting, that will prevent sending/receiving anything from the Linux system, and could explain why you aren't seeing anything?

If I send the command for the bridge shutdown, what should I see?

Probably nothing.

Normally, the Linux serial port that is connected to the AVR processor through shield connector pins 0 and 1 is running a command shell and is acting as the console sending log output. The latter is what sends the log messages you should be seeing at startup, while the former allows you to send commands to Linux once it's booted up. The command shell is also what allows the Bridge library to work. When you call Bridge.begin() in a sketch, the sketch sends a series of commands to the Linux port to launch a Python script which handles the Linux side of the communications protocol. While that script is running, the Linux serial port is tied to the script, and cannot process any shell commands. Sending the bridge shutdown command tells the Python script to exit and return to the command shell.

So, since you have just started (or are starting up the Yun) and haven't called Bridge.begin() from your sketch code, the Bridge is not running. Therefore, sending the bridge shutdown command should have no effect. (Although it may leave some garbage characters in the command shell's input buffer, causing the next command to not be understood.)

Thank you for the reasons I have not to use the symbol '-', I won't use it anymore.

In the meanwhile, I will document myself about Python scripts.

Is it right that the white LED is ON immediately and it doesn't wait one minute to switch on?

Which program language must be selected for the sketches? (now,it shows to me 'USBasp').

Thank you

muscedra:
Is it right that the white LED is ON immediately and it doesn’t wait one minute to switch on?

No. At least it doesn’t do that on mine. Is it bright white or dim? A while ago, some people were having problems with Yuns that won’t boot up, and customer service asked if the white light was on dim - if the answer was yes, they were instructed to return the Yun for exchange. I never could find out what the dim white LED meant.

Mine is off on power up, and after a minute it comes on quite brightly (brightest one out of the bunch.)

Which program language must be selected for the sketches? (now,it shows to me ‘USBasp’).

I’m afraid I don’t understand the question, and I don’t know what USBasp might be.

One more question: does your board say ‘arduino.cc’ on it, or ‘arduino.org’? The Arduino founders had a falling out at the beginning of the year and split into two companies. I have an arduino.cc board from before that time. My understanding is that the new arduino.org boards are running a slightly different version of the Linux software - I don’t know all of the differences, the only thing I know for sure that is different is the name of the initial WiFi access point (the arduino.cc boards contain the word ‘Arduino’ in the name, while the arduino.ord boards contain the word ‘Linino’), and the default login password (arduino.cc is ‘arduino’ while arduino.org is 'doghunter.) Perhaps the LED behavior might also be a difference between the system software versions? (I think it’s unlikely, but I suppose it’s possible.)

The White LED isn't as bright as the green, so I think it's dim.

My Yùn says 'arduino.cc'.

What a pity, I hoped that it was something linked to my PC or some settings I had to do...

Please,what do you mean when you say 'Customer service'? Do I have to go to my distributor?

Thank you

muscedra:
The White LED isn’t as bright as the green, so I think it’s dim.

The attached picture, poor quality as it is, shows the relative brightness of the LEDs on one of my Yuns:

  • yellow LEDs are reasonably bright
  • green “ON” is fairly dim
  • white “USB” is by far the brightest of them all

Please,what do you mean when you say ‘Customer service’? Do I have to go to my distributor?

I have no personal experience with the issue, I’m only going by other threads I’ve seen on this forum, like this one: Completely Bricked Yùn

It’s never been posted (at least not that I could find) what the resolution was or what the dim LED actually means. And just to be clear, I have no connection with either Arduino company and have no connection with the forum itself, and have no relation to any seller, distributor, or related company. I’m just another Yun user, just like you, trying to help out.

photo259.JPG

Hi

Thank you for the comprehensive knowledge, for me they have been very useful your suggestions and considerations

I've seen that there's a section called 'Support' and maybe I can send an e-mail to them, explaining my problem.

I send you the picture of my Yùn, I think the white LED is too weak.

It has been a very good event to talk with you.Thank you very much!

I've tried again to insert the picture.

I've never seen a Yun (or a picture of one) with a weak white LED, so I wouldn't be able to say if yours is one that is affected by it or not. My guess would be only a guess, and would be no better than yours.

Good luck! Let us know how it turns out.

Certainly, I will post again! Good luck!

Hi everybody,

I’ve solved my problem, in the way that my distributor changed my board with another new.
Now I can see that the white LED switches on after one minute and it is very bright ( as you told me),
while the other old Yùn had the white LED immediately on and it was dim.

Moreover I can see Yùn Access Point in my PC.

Thank you for the useful help!

(I try again to upload the image of the dim led)

Congratulations! Thanks for the update, I'm glad to hear it's working now.

Yes, the LED certainly is dim in your picture. As you can now see, that was definitely not normal.