Patent ID: 7109810

Claim:
A method of generating a time signal comprising: initializing a set of control signals in which initializing the set of control signals comprises initializing the set of control signals based on values stored in a basic input/output system (BIOS); generating a system time signal using a real time clock circuit that has a tunable oscillator for adjusting an operation frequency of the real time clock circuit, the tunable oscillator having a set of capacitors that can be independently selected based on the set of control signals; receiving a reference time signal over a network; and after the initializing, adjusting the set of control signals to modify a selection of a subset of the capacitors in the tunable oscillator to increase or decrease the operating frequency of the real time clock circuit in response to a difference between the system time signal and the reference time signal; and setting a flag to indicate whether, after rebooting of an electronic device that includes the real time clock, the set of control signals need to be initialized.