An I/O interface supports scrambling, where the scrambling can include nonlinear scrambling of the scrambling code, or dynamic bus inversion of the scrambling code, or selective switching of selected bits of the scrambling code, or a combination of these. The transmitting device includes a scrambler and the receiving device includes a descrambler. Both the scrambler and the descrambler generate a linear feedback scrambling code modified by applying one or more of the techniques mentioned above. The modified scrambling code may cause fewer than half of the scrambled output bits to be toggled with respect to a previous scrambled output. The scrambler applies the modified scrambling code to a signal to transmit. The descrambler applies the modified scrambling code to a received signal.