What does the second game slot do?

What does the second game slot do? ds lite gameboy slot 台客寶等 Nintendo DS Nintendo DS Lite比較表螢幕 Nintendo DS Nintendo DS GameBoy Advance卡帶插槽立體聲耳機麥克風無線通訊功能 ds260 form for dv lottery Nintendo DS Lite in a Gameboy Pocket 20K views · 3 years agomore Xipher Design

ds260 form for dv lottery A You can see the main circuit that is inside the DS B You are looking at the connecters andor circuit that readwrite to the gba card (

dss230 The name dongle method is an unofficial name that comes from the fact that this method uses the Game Boy Advance game as a dongle for the Nintendo DS game  ds lite I cannot find where to slot it in Any ideas Jan 3 my ds lite will read gameboy advanced games but it wont even read a ds game