Minimizing timestamp error in PTP systems
In accordance with some embodiments of the present invention, a method of minimizing timing error in a precise timing protocol system includes receiving an input 1PPS signal and a clock signal; outputting an output 1PPS signal a number of clock edges after receipt of the input 1PPS signal; adjusting the clock signal until the output 1PPS signal as jumped a clock cycle; and adjusting an offset to bring the output 1PPS signal to within a half clock period. In some embodiments, further adjustments can be made to the timestamp.
1. A method of minimizing timing error in a precise timing protocol system, comprising:
receiving an input one-pulse-per-second (1PPS) signal and a clock signal;
outputting an output 1PPS signal a number of clock edges after receipt of the input 1PPS signal;
adjusting the clock signal until the output 1PPS signal has jumped a clock cycle; and
adjusting an offset to bring the output 1PPS signal to within a half clock period.
2. A method of setting a time stamp, comprising:
receiving an input one-pulse-per-second (1PPS) signal and an input clock signal;
adjusting the input clock signal to within one half of the input clock signal;
receiving a further correction of an output of the 1PPS signal; and
providing the time stamp that accounts for the one half of the input clock signal adjustment and the further correction.
3. The method of claim 2 , wherein adjusting the input clock signal comprises: receiving the input 1PPS signal and a clock signal;
outputting the output 1PPS signal a number of clock edges after receipt of the input 1PPS signal;
adjusting the clock signal until the output 1PPS signal has jumped a clock cycle; and
adjusting an offset to bring the output 1PPS signal to within a half clock period.