1. A circuit configuration, comprising: a first input for inputting a first set of digital input data; an output for outputting digital output data; a control input for receiving a control signal; and at least first register unit and a second register unit, wherein: the circuit configuration writes, as a function of the control signal, in the first register unit at least a part of one of the first set of input data and a second set of input data, and the circuit configuration writes into the second register unit at least a part of one of the first set of input data and the second set of input data.