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Why everywhere is said that PTP synchronize phase and time together? enter image description here

phase and time are totally separate concepts. does it mean after using PTP rising edge of slave and master clocks happen simultanously? Actually I think PTP synchronizes just the time(not phase)

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    \$\begingroup\$ "phase and time are totally separate concepts". Then you don't understand one or the other. A phase shift is a time delay. \$\endgroup\$ – Olin Lathrop Jul 8 '18 at 12:28
  • \$\begingroup\$ I know, but when you talk about phase sync your clock edges should happen simulatanously, but you can be time sync and have precision of 1/f but then you are not phase sync. \$\endgroup\$ – shahriar Jul 8 '18 at 12:36
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Frequency and phase sync can both be done with PTP, usually the frequency is locked first then the phase is slipped (by slightly tweaking the frequency for a moment) to align the edges.

Often hardware in the PHY will deal with the frequency side of the problem, while you need to write some code to programmatically send commands to align the edges.

Some of the TI app notes around the DP83640 for example go into the gory details.

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