add ppu memory area to bus

src/nes/bus.rs

@@ -42,6 +42,7 @@ impl Bus
 		match addr
 		{
 			0..=0x1FFF 		=> self.ram[(addr & 0x7FF) as usize],
+			0x2000..=0x3FFF => self.ppu.upgrade().unwrap().borrow_mut().get_regsiter(addr & 0x7),
 			0x8000..=0xFFFF => self.cartridge.read_prg(addr & 0x7FFF),
 
 			_ => panic!("Tried to access invalid memory address ${:04X}", addr)
@@ -53,9 +54,10 @@ impl Bus
 		match addr 
 		{
 			0..=0x1FFF 		=> self.ram[(addr & 0x7FF) as usize] = val,
+			0x2000..=0x3FFF => self.ppu.upgrade().unwrap().borrow_mut().set_regsiter(addr & 0x7, val),
 			0x8000..=0xFFFF => self.cartridge.write_prg(addr & 0x7FFF, val),
 
-			_ => panic!("Tried to access invalid memory address ${:04X}", addr)
+			_ => { }
 		}
 	}
 }

src/nes/ppu.rs

@@ -24,6 +24,22 @@ impl PPU
 		}
 	}
 
+	pub fn set_regsiter(&mut self, addr: u16, val: u8)
+	{
+		match addr 
+		{
+			_ => panic!("Register not implemented")
+		}
+	}
+
+	pub fn get_regsiter(&mut self, addr: u16) -> u8
+	{
+		match addr 
+		{
+			_ => panic!("Register not implemented")
+		}
+	}
+
 	pub fn dot(&mut self)
 	{
 		self.screen_x += 1;