Abstract: Aspects of the disclosure provide for an apparatus. In some examples, the apparatus includes a clock generator, a clock data recovery (CDR) circuit, a state machine, and an adder. The clock generator is configured to determine a sampling clock based on a received input clock and a clock offset. The CDR circuit is configured to determine a phase of the input clock and determine CDR codes based on the determined phase and sampled data. The state machine is configured to record a first CDR code of the CDR codes at a first time, record a second CDR code of the CDR codes at a second time subsequent to the first time, and determine a calibrated offset based on the first CDR code and the second CDR code. The adder is configured to determine the clock offset according to the CDR codes and the calibrated offset.