What exactly has to be considered while flashing the router and where to get the suitable firmware, you will get to know here:
First, plug the router into the power socket with the power supply unit (1). Then connect the router to your computer via the the LAN cable (2) using one of the yellow sockets.
Currently we support different router models. First of all you have to check which firmware you need. The router type (1) and the hardware version (2) are most important. Both details can be found on the backside of your device.
The respective firmware can then be found in the Firmware Wizard list.
Now switch on the router and, after 2 minutes, go to the address
http://192.168.0.1 in your browser. A login mask shows up that asks for username and password. Enter the user
admin and the password
At the new page, select the "System Tools" entry at the left hand side and the "Firmware Upgrade". Afterwards the page should look like the following picture.
You can now select the firmware that you just downloaded via the "Browse" button. After you confirmed that the firmware should be installed, the process starts. Don't cut off the power supply from the router now otherwise the installation will fail.
After the firmware was completely installed, the router reboots. You will recognize the reboot because the LEDs blink. First, they blink wildly, then they go off.
After a few minutes, disconnect the ethernet cable from your computer and connect it again. You will now get a new address that starts with "192.168.133".
You can now configure your router via the address
http://192.168.133.1 and assign a name and coordinates.
From now on, the Freifunk router is now ready and and you can connect it to the Internet via the blue WAN port.
Source: Freifunk München