whats the use of PPS pin (ETH_pps_out) in Ethernet

[VChau]

Hi all,

I'm working on Ethernet interface with STM32F417, I Generate the code by cubeMx for Ethernet stack (lwip).

I want to know whats the use of PPS (ETH_pps_out - PB5) in ethernet because neither this pin is connected with phy nor ethernet port rf45.

[Javier1]

https://community.st.com/s/question/0D50X00009Xkgx3SAB/eth-pps-signal-generation-in-pf10

[LCE]

It has absolutely nothing to do with the ethernet hardware interface.

It is an output for use with the PTP / 1588v2 synchronization protocol, PPS is the "Pulse Per Second" kinda divided PTP clock output (derived from the PTP registers).

It can be used for evaluation (comparing several synchronized devices), or for further synchronization purposes.