A system having a transmission unit transmitting an output data signal formed from output data and related error detection code and a corresponding receiving unit. The output data signal is pre-emphasized by a pre-emphasis driver in the transmission unit. The receiving unit includes an equalizer equalizing the received output data signal and an error detector analyzing the error detection code to determine whether a bit error is present in the received data. Upon successive data transmission failures either an equalization coefficient in the equalizer or a pre-emphasis coefficient in the pre-emphasis driver are changed.