zelda ph. h. sun door (ds emulator)

Hello, i play Zelda phantom hourglass at a ds emulator. When i go to the temple of ocean king and reach the sun door the idea is to close up the ds in order to press the sea chart against the other screen which is not possible with the emulator... Anybody know how to do it at the emulator?

 

good point, lol i can see loads of people closing there monitors on the laptops and getting nothing.