Comms cape, RS485, why is there a 74LVC1G57 involved?

I am looking at capes/Comms_Cape_sch.pdf at master · beagleboard/capes · GitHub to get some inspiration for the RS485 connection that I have to make. I do not understand what the 74LVC1G57 is doing between RS485 RX and RO.

Why is that?

Regard.
Johan