Realtek Based Wi-Fi Dongles on the Beagle Bone Black (BBB)

http://nordicgroup.us/bbb/wireless/

Last Update: 30 July 2013
 

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This method is far easier and faster than the methods described at http://circuitco.com/support/index.php?title=WiFi or http://learn.adafruit.com/beaglebone/wifi. No OS update is necessary, just copy ten files over to the BBB and reboot.

To get Realtek Wi-Fi dongles working with the Beagle Bone Black, do the following:

  1. Power your BBB from the barrel jack, not from the Mini-USB jack. A Wi-Fi adapter can draw quite a bit of current and the Mini-USB connector is not designed for high-current. Use a power supply that is able to supply at least 2A. See http://www.mpja.com/5-Volt-DC-Plug-Power-Supply-4A-Regulated/productinfo/18520%20PS/ for a good power supply. Also note that the BBB will operate at a higher frequency if you use the barrel jack for power (be thankful that the BeagleBone hardware designers did not use the awful power distribution scheme that is present on the Raspberry Pi, I just wish that they had not even provided a way to power the board from USB).

    If you are using the BBB with an HDMI monitor and a USB keyboard/mouse then you are going to be using a USB hub because you'll need another USB port for the Wi-Fi adapter, so you should be using a powered hub, not a hub powered by the BBB. You might get by with an unpowered hub provided you provide sufficient power to the BBB. I don't know how much current the USB host port on the BBB can supply. 500mA is guaranteed, but normally USB host ports can provide quite a bit more than that before tripping the over-current protection. I use a Motorola Lapdock with the BBB and it has two USB host ports. One can power the BBB and one can be used for the Wi-Fi dongle. The Micro-USB male connector on the Lapdock connects to the USB-A host port on the BBB, using a cable that has the power conductor cut (for some reason, the Lapdock keyboard, mouse, and USB ports will not work with the BBB if +5 is present).

     

  2. Click on the symbol of a network cable in the upper right of the screen (to the left of the date), click on Preferences, and you will see only a choice for Wired Networks. Do nothing.

     

  3. On the BBB, Create a directory named rtlwifi under /lib/firmware/  (go to the /lib/firmware/ directory and type mkdir rtlwifi).

     

  4. With the BBB plugged into a wired network use the Chromium browser to go to:
    https://git.kernel.org/cgit/linux/kernel/git/firmware/linux-firmware.git/tree/rtlwifi. Ignore the security warning if you receive one. I have also made them available from my web site, see     http://nordicgroup.us/bbb/wireless/rtlwifi/ where they are easier to download.

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  5. Download all 10 files into: /lib/firmware/rtlwifi/. The way you download is to, one by one, double-click the file then double-click on "plain" and the file will be downloaded into the download directory. You can then copy the files over to the /lib/firmware/rtlwifi/ directory (I could not figure out how to change the default download location on the Chromium browser). If you don't have a wired Ethernet connection then you could download the files onto a MicroSD card and stick the MicroSD card into the BBB and copy the files over to /lib/firmware/rtlwifi/. You can also plug the BBB into a computer (use the Mini-USB port) with network access and copy the files over, then on the BBB copy the files from the BEAGLEBONE directory to /lib/firmware/rtlwifi/.

     

  6. Plug in the Wi-Fi dongle.

     

  7. Reboot. The LED on the dongle should light up.

     

  8. Click on the symbol in the upper right of the screen (to the left of the date), click on Preferences, choose Wireless Networks, select your network and enter the Wi-Fi password (if any).

     

  9. I have successfully used the following Wi-Fi dongles with Realtek chips:

Edimax EW-7811Un  http://www.edimax.com/en/produce_detail.php?pd_id=347&pl1_id=1 This uses the Realtek RTL8188CUS, but it uses the driver for the RTL8192CU. Amazon sells these for $12, http://www.amazon.com/dp/B005CLMJLU. Supports up to 150 Mbps (802.11n). Very small. This device is also sold as the following: Edimax EW-7811GLn, EW-7811Un, EW-7811UWn, GWU-H811GLn; Airlink101 AWLL5088; Sitecom WL-365; GETNET GN-521U.

GMYLE WFUS11N06203V1. This uses the Realtek RTL8191US chip and includes a high gain 5dBi Antenna. Amazon sells these for $14, http://www.amazon.com/dp/B003Y6UNI6/. Supports up to 300Mbps. It's a lot larger than the Edimax EW-7811, even without the external antenna attached, but if you are trying to connect to a network that's not very close it may be worth the extra size. These have become popular when using an embedded board as a print server or file server.

Notes

  1. For the BBB, do not follow the Adafruit instructions designed for the original BeagleBone board (BeagleBone White). Those instructions will not work for the BBB and you will destroy the eMMC image on your BBB and have to reflash it. My instructions may work for the Beagle Bone White but I don't have one to try it on.
  2. Be aware that due to a bug in the Angstrom Linux version 0620, the Beaglebone Black will not work with the Motorola Lapdock's HDMI video; 0508 does work properly with the Lapdock. I spent many hours on this issue and was about to RMA my board.
  3. I have only tried the BBB using an HDMI monitor and a USB keyboard and trackpad and hub (Motorola Lapdock). I have not tried using an ssh client or a VNC server. I found that I needed to cut the power wire inside the USB cable going to the Beaglebone in order for the Lapdock to work, apparently either the Lapdock does not like being powered by an external USB port or the BBB does not like being powered by the Lapdock via the USB host port.
  4. If you are using the Motorola Lapdock as a monitor/keyboard/trackpad/hub, the dongle works fine plugged into one of the Lapdock's USB ports.
  5. I have not tried these dongles with an unpowered USB hub.The Edimax EW-7811un works in the Raspberry Pi's USB port as long as the Raspberry Pi is properly powered.
  6. I am not a Linux expert and I doubt if I could answer any questions regarding getting other Wi-Fi dongles to work. I'm amazed that I was able to get it working at all. The BBB is not as user friendly as the Raspberry Pi.
  7. I have not been able to get the 06.20 image for the BBB to work on my board. I had to flash the 05.08 image. I am pretty certain that there is a problem with the 06.20 image's HDMI configuration and that it is not compatible with the screen on the Motorola Lapdock.
  8. See http://www.mpja.com/5-Volt-DC-Plug-Power-Supply-4A-Regulated/productinfo/18520%20PS/ for one suitable supply with the proper connector, $7. Also sold at Jameco for $13, see http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_2135451_-1. and at Amazon (if they have any left) for $5.95 with free shipping http://www.amazon.com/dp/B008NTJWF4.
  9. I SPIT on Mini-USB or Micro-USB for power connections, just kidding, but a lot of problems with the Raspberry Pi are caused by its lack of a proper power connector and by errors in its documentation with regard to how much current is needed to power the board when USB devices are plugged in. The big problem with using USB for power is that the conductors inside a USB cable are typically very tiny gauge wires and there are significant losses between the power supply and the Raspberry Pi. You can buy USB cables with larger gauge wire but they are not all that common.

Also see my web page on Raspberry Pi Power Issues http://nordicgroup.us/rpi/power/. Much of the advice applies to the BeagleBone as well, though thankfully the BeagleBone designers did a much better job when it comes to power. This page also details the use of the Motorola Lapdock.