Dallas temperature sensor DS18S20 with the ATmega32-16PU

Thanks michinyon for your explanation.

No, there is no output about that it detected a one-wire device.

Just a remark for my setup.
I use an UBSTinyISB to flash the controller which is an ATmega32-16PU and you find the corresponding datasheet here: http://www.atmel.com/Images/doc2503.pdf

When I looked at your answer I think you mixed up the ATmega32-16PU with the ATmega328P. The latter uses PD0 and PD1 for RX/TX, respectively and is used within the Arduino.