US Patent 10164805 Characterization of decision feedback equalizer taps

Various embodiments, disclosed herein, can include apparatus and methods to characterize taps of a decision feedback equalizer of a data receiver. In characterizing the taps of the decision feedback equalizer of the data receiver, a signal can be transmitted to the data receiver and the received data can be iteratively sampled at an output of the decision feedback equalizer. The sampling can include stepping a sample time relative to arrival of the received data and stepping a reference voltage level to which the received data is compared. Values of the sampled data can be compared with known correct values and such measurements can be used to characterize the taps. Additional apparatus, systems, and methods are disclosed.