Methods and systems are described for generating, with a local oscillator and an adjustable phase interpolator, a data-sampling clock and a variable-phase-offset eye-measurement clock, forming a received data signal using a multi-input comparator, generating, using a data slicer and the data sampling clock, a receive sample of the received data signal, and generating, using at least one eye slicer and the variable-phase-offset eye-measurement clock, a plurality of eye characteristic measurements by adjusting a sampling threshold of the at least one eye slicer and a phase offset of the variable-phase-offset eye-measurement clock.