ESP32-POE - 2 PCF8575 expansion board

I want to use ESP32-POE with 2 of PCF8575 16 pins extender board

What I wounder are how PCF8575 boards know what adress they get?
I will use this board to control 2x16 relay boards.
Now I use a arduino Mega 2560 with homeseer over ethernet. but i want to change over to HA totally instead of having running to system.

I would be very happy if someone could help me little with thw code also.
If you have more question about how the my system work jsut ask then.

You have three addess pins: A0, A1 and A2. With this set either to GND or +Vcc you set address of the chip.

Thx. it there address tabel somewhere to see how the address pin should be use?
I have also start to look in to use mega 2560 as port expander and control it over rs232
sounds easier to connect a esp 32 poe too existing setup and control the mega boards instead of making a port expander sheild.

Look in original datasheet of the chip, it’s all written there. Search for PCF8575 datasheet pdf file