STM32H7 Nucleo board - Ethernet PPS output

Can anyone provide sample code for Ethernet PPS output signal generation?

I use Nucleo board, pin PB5 (CN7 connector).

I use 43 value for sub second increment register

My PPS settings:

 ETH->MACPPSIR = 50000000 - 1;//PPS interval register (1 tick - 20ns, 1sec = 1000000000ns - 50000000 ticks)

 ETH->MACPPSWR = 10000000 - 1; //PPS width register (1 tick - 20ns, 200ms - 10000000 ticks)

But I can not see PPS on oscilloscope