A data processing apparatus comprises a data processing module, which can
be operated in a first operating mode with a normal power consumption and
a second operating mode, wherein a power consumption of the data
processing module in the second operating mode is smaller than the first
power consumption or equal to 0. The data processing apparatus further
comprises means for signaling a possibility that the data processing
module can be placed into the second operating mode, means for providing
a time-varying control signal, means for placing the data processing
module from one data operating mode to the other, wherein means for
placing is formed to place the data processing module into the other
operating mode, when means for signaling signals the possibility and the
control signal fulfills a predetermined condition.