TMDSIDK437X: TMDSIDK437X - Using one 1G RAM instead of two 512 MB RAMs?

Part Number:TMDSIDK437X

Dear all,

I would like to trim down the TMDSIDK437X schematics to use it for Profinet, Profibus, and Ethercat Communication. In the schematic on page 6. there are two 512 MB RAMs depicted. Should I also use two RAMs for my design or is one 1GB RAM sufficient? I am just trying to understand the motivation behind using two RAMs.

Many thanks for your input!