diff --git a/sources/Memory/MemoryBus.cpp b/sources/Memory/MemoryBus.cpp
index 837146d..6ff8d2b 100644
--- a/sources/Memory/MemoryBus.cpp
+++ b/sources/Memory/MemoryBus.cpp
@@ -48,12 +48,14 @@ namespace ComSquare
 	void MemoryBus::_mirrorComponents(SNES &console, int i)
 	{
 		this->_memoryAccessors.push_back(Memory::MemoryShadow::createShadow(console.wram, i, i + 0x2000));
+		this->_memoryAccessors.push_back(Memory::MemoryShadow::createShadow(console.ppu, i + 0x2100, i + 0x2140));
+		this->_memoryAccessors.push_back(Memory::MemoryShadow::createShadow(console.apu, i + 0x2140, i + 0x2144));
 		this->_memoryAccessors.push_back(Memory::MemoryShadow::createShadow(console.cpu, i + 0x4200, i + 0x4220));
 	}
 
 	void MemoryBus::mapComponents(SNES &console)
 	{
-		// The WRam is always mapped in the bank 7E and 7F, no matter the memory mapping mode.
+		// The WRam and PU registers are always mapped at the same address no matter the mapping mode.
 		console.wram->setMemoryRegion(0x7E0000, 0x7FFFFF);
 		this->_memoryAccessors.push_back(console.wram);
 
@@ -67,14 +69,15 @@ namespace ComSquare
 		this->_memoryAccessors.push_back(console.cpu);
 
 		// TODO implement DMA & HDMA (4220 to 4300)
+		// TODO implement Joys.
 
-		//Mirror the first $2000 bits of the WRam to all banks of the Q1 & Q3.
-		for (uint24_t i = 0; i < 0x400000; i += 0x10000) {
+		// Map to the quarter 1.
+		for (uint24_t i = 0; i < 0x400000; i += 0x10000)
 			this->_mirrorComponents(console, i);
-		}
-		for (uint24_t i = 0x800000; i < 0xC00000; i += 0x10000) {
-			this->_memoryAccessors.push_back(Memory::MemoryShadow::createShadow(console.wram, i, i + 0x2000));
-			this->_memoryAccessors.push_back(Memory::MemoryShadow::createShadow(console.cpu, i + 0x4200, i + 0x4220));
-		}
+		// Map to the quarter 3.
+		for (uint24_t i = 0x800000; i < 0xC00000; i += 0x10000)
+			this->_mirrorComponents(console, i);
+
+		// TODO should map sram, cartridge etc via the mapping mode of the cartridge.
 	}
 }
\ No newline at end of file
diff --git a/sources/Memory/MemoryBus.hpp b/sources/Memory/MemoryBus.hpp
index 3ad6c01..2494e56 100644
--- a/sources/Memory/MemoryBus.hpp
+++ b/sources/Memory/MemoryBus.hpp
@@ -23,7 +23,7 @@ namespace ComSquare
 		std::shared_ptr<IMemory> getAccessor(uint24_t addr);
 		//! @brief The last value read via the memory bus.
 		uint8_t _openbus = 0;
-		//! @brief Mirror components to other banks. (Used by the mapComponents method).
+		//! @brief WRam, CPU, PPU & ALU registers are mirrored to all banks of Q1 & Q3. This function is used for the mirroring.
 		//! @param console All the components.
 		//! @param i Base address for the mirrors.
 		inline void _mirrorComponents(struct SNES &console, int i);