Deactivate the LEDs of your Radxa Rock

The Rock’s frequently blinking lights can be an annoying source of light pollution. Here is how to turn most of them off. However, the ethernet and wifi leds can only be soldered them out.

On the newer images, the 3 Rock’s LEDs are configured as LED class devices, so edit rc.local

and set them to none using this snippet:

For the older images, the LEDs have to be set via the GPIOs:

make sure that you add those lines before the exit 0 statement in rc.local.

Ubuntu Server Kernel 3.18 on Radxa Rock Pro

If you own a Radxa Rock Pro you have surely had enough trouble with the antiquated 3.0.36 kernel and the many hacked drivers to get it working somehow. Thanks to the work of Heiko Stübner and other kernel developers finally current kernels can be used on this great ARM development board. Keep in mind that video and audio drivers are not mainlined yet. Here is a howto:

Now determine the disk number of your microsd card, unmount the disk and flash the image with dd. Here are the instructions from an OS X perspective:

Make sure you use /dev/rdiskX as raw access is up to 20x faster. After unmounting, you can safely remove the microsd card and put it in your Radxa Rock Pro. You can login with rock/rock:

Next, expand the filesystem with this shell script or manually:


When the system is back up again, the filesystem has to be resized to the new partition sizes:

For me that didn’t work out because there were permission issues:

resize2fs 1.42.9 (4-Feb-2014)
Filesystem at /dev/mmcblk0p1 is mounted on /; on-line resizing required
old_desc_blocks = 1, new_desc_blocks = 2
resize2fs: Permission denied to resize filesystem

To fix this on OS X install e2fsprogs to get resize2fs:

to avoid replacing some OS X provided files they are not linked into /usr/local.

Unmount the disk:

Check the partition for errors and resize:

For more details on the process see this guide:

First update your locales unless you want lots of locale warnings:

remove apache2 and mysql if you don’t need them:

then upgrade your system and install some frequently used tools:

Now Add a new user:

Log on as the new user an delete the old one:

To easily access all your computers you may want to authenticate yourself with certificates.

On a Mac, first install the missing ssh-copy-id:

Then you can copy your public key to the ssh hosts you frequently need by:

Now configure you ethernet in a way that your MAC won’t change with every restart:

The content should look like:

auto eth0
allow-hotplug eth0
iface eth0 inet dhcp
hwaddress ether 01:02:03:04:05:06

Make sure the hwadress is valid and unique.

To get wlan running:

and add:

ssid="your ssid name"
psk="your wireless password"

If you have several Radxa Rocks, you may want to change their hostnames:

Set up the correct time zone and get a ntp update:

this is important because otherwise the SSL certificates won’t work.

To set up git:

and copy the contents into the ssh keys section of the github preferences.

To configure zsh:

To get AFP filesharing:

Additional folders can be shared by editing AppleVolumes.default:

and adding a line like

/media/microsd/media “Media”

and restarting the netatalk service with:

Compile missing kernel modules for Radxa Rock Pro

If you want to use an Arduino with your Radxa Rock Pro Kernel 3.18 you will need to build some kernel modules by hand. Here is a short howto. Strangely this didn’t work directly on the Radxa Rock Pro so I had to cross compile on a Ubuntu 14.10 system:

Navigate to Device Drivers -> USB Support -> USB Serial Converter Support -> and select USB FTDI Single Port Serial Driver with „m“ and save to .config

Transfer the kernel model to your radxa with a method of your choice and and test them:

If everything works you can install the modules permanently:

then you can load the kernel modules with:

and/or add them permanently to /etc/modules:


You may get an error like:

with dmesg you see:

or you can get more information about the module with:

filename: /home/phoenix/ftdi_sio.ko
license: GPL
description: USB FTDI Serial Converters Driver
author: Greg Kroah-Hartman <>, Bill Ryder <>, Kuba Ober , Andreas Mohr, Johan Hovold <>
alias: usb:v0403pD012d*dc*dsc*dp*ic*isc*ip*in*
depends: usbserial
vermagic: 3.19.0-rc5+ SMP mod_unload ARMv7 p2v8
parm: ndi_latency_timer:NDI device latency timer override (int)

In my case you can see the problem was that the default kernel is only:

So I should have gotten an older source…