WiFi-Stick Edimax EW-7811Un for the RaspberryPi (with Arch Linux ARM)

This is how it shows up in the kernel log / dmesg on Ubuntu:

[712886.216957] usb 1-1.2: new high-speed USB device number 5 using dwc_otg
[712886.318980] usb 1-1.2: New USB device found, idVendor=7392, idProduct=7811
[712886.319014] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[712886.319034] usb 1-1.2: Product: 802.11n WLAN Adapter
[712886.319051] usb 1-1.2: Manufacturer: Realtek
[712886.319083] usb 1-1.2: SerialNumber: 00e04c000001
[712886.962139] usbcore: registered new interface driver rtl8192cu

Driver on Arch Linux

When I wrote this post, Arch Linux ARM didn't come with the needed drivers. As of 2013-06-03 it actually does. So you just have to plug it in (reboots my RPi when doing it while powered on :( ).

Check that wlan0 is in the output of ip addr. Then your good to configure your WiFi connection(s).

Creating the Wifi Connection

  1. Run wifi-menu and set up your WiFi connection.
  2. Afterwards run netctl start profile-name and netctl start profile-name. Really easy.
    See here for more detailed help.

Performance

The performance of this WiFi Stick is not very impressive. Compared to my Siemens Gigaset USB Adapter 54 the average ping is considerably higher:

Average of 100 ping rounds to google.com:

Wired Connection Edimax EW-7811Un Siemens Gigaset USB Adapter 54 v2
2.22 ms 11.42 ms 3.46 ms

So Edimax' ping time is on average 7.96 ms higher than Siemens Gigaset's one!

hostapd Mode

You need a modified hostapd version (instructions for Arch Linux):

su pklaus
cd
wget https://aur.archlinux.org/packages/ho/hostapd-8192cu/hostapd-8192cu.tar.gz
tar -xf hostapd-8192cu.tar.gz 
cd hostapd-8192cu/
makepkg -s
exit
pacman -U ~pklaus/hostapd-8192cu/hostapd-8192cu-0.8_rtw_r7475.20130812_beta-3-armv7h.pkg.tar.xz

I didn't have good experiences with it.

References

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