RPi3 Wifi Channel 12 and 13

Dear All,

I came across a problem today getting on to a WiFi access point that was using wifi channel 13. It seems that this is an issue on the RPi3. e.g http://tosbourn.com/get-channels-12-and-13-on-the-raspberry-pi-3/ or https://www.raspberrypi.org/forums/viewtopic.php?t=36961&p=308560.

Applying the fix including running rpi-update seems like it may change the Emlid image firmware and I’m guessing may cause issues? Has anyone experienced this problem? Advice would be much appreciated!

Cheers,
Rodger

Dear Roger,

It is now safe to run apt-get.

rpi-update breaks the Emlid setup which is kind of what I expected:

After updating the kernel and firmware running ArduCopter-quad reports:

SPI: unable to open SPI bus /dev/spidev0.2: No such file or directory

Reverting back to the original kernel / firmware by copying all files from /boot.bak to /boot fixes the problem and ArduCopter-quad runs again. The channel fix for the wifi firmware needs to be patched into the Emlid kernel.

Cheers,
Rodger

To get channel 12 and 13 working do:

sudo apt-get update
sudo apt-get dist-upgrade
sudo reboot

Confirm that kernel 4.4 is running

uname -a

Create or edit:

sudo vim /etc/modprobe.d/cfg80211.conf

insert or replace the line:

options cfg80211 ieee80211_regdom=DE

use the region code for your region. DE is allowed 12 and 13 as is GB and NO.

sudo reboot

once it is back again

sudo iwlist wlan0 channel

to confirm that 12 and 13 are now available.

Using rpi-update to get the latest firmware as recommended in some articles is a bad idea and breaks the emlid image. Using rpi-config to set the internationalisation for wifi does not work. The manual edit above is still needed.

Cheers,
Rodger