A decoding circuit and associated method are provided for decoding a biphase signal. The decoding circuit may include a precharging register to precharge a pair of states of the biphase signal, where a state of the pair of states is precharged at each pulse of a periodic precharging signal. The decoding circuit may further include a verification circuit to compare the two states of the pair of states and give an active error signal if the two states are equal.