Dropouts with USB WiFi (802.11b/g/n) Module: For Raspberry P

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Juggler00
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by Juggler00 »

Never mind, seems Raspbmc already has it in the install:

Code: Select all

pi@raspbmc:/etc/modprobe.d$ cat 8192cu.conf 
options 8192cu rtw_power_mgnt=0 rtw_enusbss=0
Now I'm wondering what the problem is... Here is a video of the boot, not sure if anyone has the patience to watch it to see if they can help me debug?
http://www.youtube.com/watch?v=A5POhLVO ... pp=desktop

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adafruit_support_rick
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by adafruit_support_rick »

You can't disable power management on the Pi.
Have you tried running the WiFi dongle through a self-powered usb hub?
What are the exact symptoms you're having?

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adafruit_support_rick
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by adafruit_support_rick »

So, the dongle keeps spontaneously disconnecting. It seems to be working otherwise. Try connecting it through a self-powered hub.

Juggler00
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by Juggler00 »

I'll give that a try, thanks. I thought this particular adapter drew small enough power that it didn't require such a hub—partly the reason I got it and your power adapter.

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adafruit_support_rick
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by adafruit_support_rick »

Usually, it works. But the usb power on the pi is kind of marginal for wifi - maybe your particular Pi is a little weak.

Juggler00
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by Juggler00 »

Interesting... I learnt something today. As you suggested, when I tried the WiFi dongle with a different Pi, no problems. Thanks for your help!

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cactusmonkey
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by cactusmonkey »

I just wanted to say that my problem resolved after running "sudo apt-get update", "sudo apt-get upgrade" and rpi-update . Internet has been robust.... strange, but I am happy that it is fixed.

Darknesss
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by Darknesss »

I was having this wifi dropout issue as well since recently.

It worked flawless for a year or so, but I recently moved so now I have a different wifi router. After configuring the wifi to autoconnect to the new network, I updated debian and was having issues from then on. Could it be an update that enabled the power management?
I will try with my old router as well to see if the new one is triggering issues.

After changing the power management setting, the wifi does not seem to drop out any more, but now the raspberry pi is experiencing unexpected reboots instead.
This is less of an issue since I can still reach it after the reboot instead of becoming unreachable due to the dropout but still very annoying and not good for the filesystem.

Has anyone experienced such reboots after disabling the power management?
Any way to diagnose what's going on that triggers the reboot (I suppose the watchdog kicks in for some reason?)?

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adafruit_support_rick
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by adafruit_support_rick »

Check your power supply. Use a voltmeter to check the voltage between TP1 and TP2:
http://elinux.org/R-Pi_Troubleshooting# ... r_problems

Darknesss
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by Darknesss »

Hmm, I must admit that I was using my other power supply when testing the power management modification. This power supply is normally used for my other raspi that is just using ethernet instead of wifi.

I will check this, thanks :-)

Darknesss
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by Darknesss »

it looks like the power supply might indeed be the problem. Measuring the voltage, I only got 4.45V, the other power supply that I use normally for this board gives 5.05V.

Now I know why my raspbmc was rebooting from time to time :-P

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adafruit_support_mike
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by adafruit_support_mike »

That is about the middle of the 'low-power flakiness' zone. Video seems to drop out around 4.7v, and by the time you get down to 4.25v the RasPi usually can't even boot.

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judson
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by judson »

I've been having dropouts on my Edimax 7811cu. I tried the fix of adding 8192cu.conf to modprobe.d; it helped some, but I still lost connections. Another forum suggested setting rtw_enusbss=0, and that seems to be working better.

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paulf8080
 
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Re: Dropouts with USB WiFi (802.11b/g/n) Module: For Raspber

Post by paulf8080 »

It's not xmas lights, but some suggestions here:
http://www.pcworld.com/article/3011915/ ... -will.html

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