logic analyzer with ZYBO

Hi everyone

Ive been trying alot of things with my new Zybo board. Ive gotten 
through the most basic tutorials and got stuck when trying to write to 
ram (or similar). I cant find much documentation on Communication (PL to 
PS) or writing to memory.

What I want to do in the end:
Read the Pmod pin status and send it to the ARM-core (which is running a 
linux).

As a first test i would like to be able to write the state of the ZYBO 
buttons to a file/memory so i can access it from linux.

Does anyone have any tips on how to proceed with this?

Thank you

Chrys