Maybe a year ago I threw my realtek dongles in the garbage after pulling my hair out for several days and bought a few cheap atheros ones. I have never had WiFi issues ever again. Plug and play and everything...
Maybe I could have gotten the realtek divers to work but my time was better spent on other things... As a bonus the atheros dongles support monitoring mode in wireshark so they have proved immensely useful in other regards for sniffing 2.4 GHz traffic at WiFi events... On Aug 22, 2014 12:56 AM, "Tony DiCola" <[email protected]> wrote: > Thanks, please don't take this the wrong way but that reply really doesn't > help the conversion. If you read the thread I mention: > > "- Yes I'm aware of the HDMI ground and power plane issue with wifi > dongles, I have the wifi dongle attached to a small USB hub that moves it > away from the BBB." > > I also describe that I found the problem is the 3.8 kernel in the official > Debian image is very old and has serious RTL8192CU bugs. Upgrading my > kernel to 3.15.10 gave me perfect reliability with the RTL8192CU adapter > (just like on the Raspberry Pi). > > The core question I have is, is the 3.15.10 kernel ready for prime time or > is work being done to backport fixed RTL8192CU drivers to the 3.8 kernel > (as I saw some recent traffic on the kernel github repo)? > > I ask because I'd like to help educate folks on how to get wifi working on > the BBB by writing a nice guide for Adafruit's learning system (like they > have for the Raspberry Pi), but right now it doesn't seem like the official > Debian image with the 3.8 kernel is really usable with Realtek adapters. > > > On Fri, Aug 22, 2014 at 12:43 AM, William Hermans <[email protected]> > wrote: > >> Well instead of reading that huge wall of text I will just say that this >> has been discussed on these group many times, and disabling hdmi has been >> proven to fix this issue by multiple people. If thats not an option then >> add a short USB extension cable to get your wireless device away from the >> ground plane on the board. >> >> >> On Fri, Aug 22, 2014 at 12:24 AM, Tony DiCola <[email protected]> >> wrote: >> >>> Oh forgot to mention on the hardware side I'm powering the BBB with a 5V >>> 10amp supply so there should be no power issues at all (it's a bit of a >>> monster supply). >>> >>> >>> On Friday, August 22, 2014 12:10:00 AM UTC-7, Tony DiCola wrote: >>>> >>>> Hey all, I've been trying to track down why my wifi dongle doesn't work >>>> reliably on boot and think I've narrowed it down to the drivers in the >>>> official Debian 3.8 kernel being old and buggy. >>>> >>>> First, the hardware I'm using: >>>> - Rev C BeagleBone Black, running the official Debian image from here: >>>> http://beagleboard.org/latest-images >>>> (side question, is the 5-14-2014 image on that page really the most >>>> recent official Debian build?) >>>> - Wifi dongle is an Edimax 7811Un, which is a RTL8192CU chipset. Very >>>> popular and works perfectly with a Raspberry Pi. >>>> - Yes I'm aware of the HDMI ground and power plane issue with wifi >>>> dongles, I have the wifi dongle attached to a small USB hub that moves it >>>> away from the BBB. >>>> >>>> My problem is that the wifi connection never reliably starts on boot. >>>> I always have to log in and run ifdown wlan0 & ifup wlan0 to get it to >>>> connect. My /etc/network/interfaces is configured in the standard way to >>>> access my AP (exactly how I've configured Raspberry Pi's which work fine), >>>> and for completeness the block of config looks like: >>>> >>>> # WiFi Example >>>> auto wlan0 >>>> allow-hotplug wlan0 >>>> iface wlan0 inet dhcp >>>> wpa-ssid "my AP name" >>>> wpa-psk "my password" >>>> >>>> I ran some experiments to reboot the BBB (just using the reboot >>>> command) multiple times and count how often the wifi connection would come >>>> up successfully on boot. The results were not good, here's what I saw: >>>> - With "auto wlan0" and "allow-hotplug wlan0" in >>>> /etc/network/interfaces 6 out of 13 attempts succeeded: success rate of >>>> 46%. >>>> - With only "auto wlan0" in /etc/network/interfces 8 out of 13 attempts >>>> succeeded: success rate of 62%. >>>> - With the dongle connected directly to the USB port (i.e. not through >>>> the hub) only 4 out of 13 attempts succeeded: success rate of 31%. >>>> >>>> I did all I could to find any information from dmesg and syslog for the >>>> failed attempts, but there's no info there. When the connection works on >>>> boot I see messages about the RTL8192CU module and then the wlan connection >>>> coming up. When the connection does not work I see the same messages about >>>> the RTL8192CU module but none of the wlan connection messages. There are >>>> no errors or failures at all in the log. It really feels like a timing or >>>> internal issue with the RTL module. If there is some other log I should be >>>> looking at please let me know and I will check it out. >>>> >>>> For comparison I ran the same test with the same wifi adapter on a >>>> Raspberry Pi running the latest Raspbian OS image. It worked fine and >>>> brought the wifi connection up all 13 times, success rate of 100%. >>>> >>>> At this point I was really confused why the BBB could not reliably >>>> bring up a wifi connection at boot. Looking a little closer the big >>>> obvious difference between the BBB and Pi is the kernel version. On the Pi >>>> it's using kernel 3.15.3 whereas the BBB is running the 3.8 kernel. >>>> Looking at the RTL8192CU source on kernel.org I can't find the 3.8 >>>> kernel source, but at least comparing the 3.10 kernel to mainline there are >>>> quite a few fixes in the more recent kernels but not in the older ones. >>>> >>>> To really confirm it was the 3.8 kernel I used Robert Nelson's upgrade >>>> script to take my BBB to the 3.15.10-bone7 kernel (script from here >>>> https://rcn-ee.net/deb/wheezy-armhf/v3.15.10-bone7/). After upgrading >>>> the kernel I ran the same reboot test and surprise, surprise the BBB >>>> brought up the wifi connection 13 out of 13 times, success rate of 100%. >>>> >>>> So long story short it seems like at least for Realtek adapters the >>>> official Debian image's 3.8 kernel has some serious issues. I'm curious is >>>> this a known issue or something being worked on right now? >>>> >>>> I noticed on the BBB kernel github there was just recently a commit >>>> yesterday to add perhaps a backport of later RTL8192CU drivers to the 3.8 >>>> kernel (looking at https://github.com/beagleboard/linux/tree/3.8/ >>>> drivers/net/wireless/rtl8192cu ). Is this true that later RTL wifi >>>> drivers are being ported back to the 3.8 kernel? >>>> >>>> Finally, is there any suggestion for what folks who use the RTL8192CU >>>> or other RTL wifi adapters should do to use them right now on the BBB? Is >>>> the 3.15.10-bone7 kernel stable enough for normal use? (like using GPIO, >>>> loading and unloading device tree overlays, etc) >>>> >>>> For better or worse the Realtek wifi adapters are quite common (folks >>>> like Adafruit only sell Realtek wifi adapters because they are known to >>>> work with the Pi) and many folks coming to the BBB from the Pi are likely >>>> trying to use them. I have a feeling many of the issues people have >>>> getting wifi to work with the BBB are related to problems with the 3.8 >>>> kernel driver. >>>> >>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to a topic in the >> Google Groups "BeagleBoard" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/beagleboard/IyeMT8j94mQ/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> [email protected]. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. 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