Patent ID: 7752478
Filing Date: 2010-07-06
Classification: G06F

Abstract:
1. An apparatus for tracking a real time clock comprising: a delay element adapted to receive a first clock signal and provide a second clock signal, wherein the second clock signal is delayed with respect to the first clock signal; a quadrature interface, the quadrature interface including a first input and a second input, wherein the first input is adapted to receive the first clock signal and the second input is configured to receive the second clock signal; and control logic adapted to provide a state machine including four states, the four states respectively corresponding to a 2-bit gray code and wherein a current state is selected by determining a correspondence of the first and second inputs to the 2-bit gray code, wherein the control logic is further adapted to provide a counter, the counter being adapted to increment upon a transition between a first state and a second state of the state machine.