First, download and install our public key
wget -q http://apt.libreems.org/apt.libreems.org-pub.asc -O- | sudo apt-key add -Our key fingerprint is:
CD07 82F4 F24C FD0B 7B18 8D1B 4428 ADA1 76FC 5FCC LibreEMS Build Team (Build Team)
Then select one of the following lines that matches your debian or ubuntu distribution (click on them to download an appropriate file for your system, then copy into /etc/apt/sources.list.d)
deb http://apt.libreems.org/ vivid custom deb http://apt.libreems.org/ utopic custom deb http://apt.libreems.org/ trusty custom deb http://apt.libreems.org/ precise custom deb http://apt.libreems.org/ lucid custom deb http://apt.libreems.org/ stretch custom deb http://apt.libreems.org/ wheezy custom deb http://apt.libreems.org/ jessie custom deb http://apt.libreems.org/ sid custom
NOTE!! If you are running behind a deb proxy like apt-cacher-ng or squid-deb-proxy you need to add "apt.libreems.org" to its list of allowed mirrors and restart it before the next step
Then to install the LibreEMS ToolChain (only needed if you are compiling firmware sourcecode) do the following:
sudo apt-get update sudo apt-get install mc9s12x-toolchain