phase difference between two signals

how can i calculate phase difference between two analog signals usings arduino uno

Measure the time difference between zero crossings and convert to degrees of phase difference.

I've deleted your other cross post @majeedjan.

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Thanks in advance for your cooperation.

1. From the two analog waves (Fig-1), get two zero crossing detectors of TTL level.

2. Use v1 to interrupt the MCU over INT0-pin and start TC0 to count 16 MHz clock of MCU.

3. Use v2 to Stop TC0.

4. Read counts of TC0 which is proportional to phase diffrence between v1 and v2.

5. Use the following Empirical Formula to find phase difference/power factor in degrees from the counts of Step-4.

pf (power factor) = cos theta = 0x2710 - 0x3A*(counts2/(0xB40xB4)).