System

– Get a good SDCARD, any SDHC 16GB Class 10 – Get an Image I have choosen the Raspbian – Image to sdcard: gparted /dev/sde delete all write add fat32, write dd bs=4M if=2014-01-07-wheezy-raspbian.img of=/dev/sde

Temperatur-Sensor

– Install WiringPi & gpio
git clone git://git.drogon.net/wiringPi
cd wiringPi
./build uninstall
./build
- Test gpio
gpio -v
gpio readall

vi /boot/config.txt 
dtoverlay=w1-gpio,gpiopin=4,pullup=on

vi /etc/modules
w1-therm
w1-gpio pullup=1
  reboot   wiring diagram: Resistor: 4,7k   Sensor: something like: cat /sys/bus/w1/devices/10-000802c2dceb/w1_slave will output: 2d 00 4b 46 ff ff 03 10 dd : crc=dd YES 2d 00 4b 46 ff ff 03 10 dd t=22562 write a bash script:
#! /bin/bash
tempread=`cat /sys/bus/w1/devices/10-000802c2dceb/w1_slave`
temp=`echo $tempread | egrep -o '.{5}$'`
temp2=`echo "scale=2; $temp / 1000" | bc`

echo $temp2
will output: 22.68