diff --git a/fpt/src/memory/lib.rs b/fpt/src/memory/lib.rs
index c54cfe9..0f25900 100644
--- a/fpt/src/memory/lib.rs
+++ b/fpt/src/memory/lib.rs
@@ -123,8 +123,26 @@ impl Bus {
             self.memory().cartridge.borrow().read(address)
         } else if address == map::JOYP {
             self.joyp()
-        } else {
+        } else if map::IO_REGISTERS.contains(&address) {
+            self.memory().mem[address as Address]
+        } else if map::VRAM.contains(&address) {
+            self.memory().mem[address as Address]
+        } else if map::HRAM.contains(&address) {
+            self.memory().mem[address as Address]
+        } else if map::WRAM.contains(&address) {
             self.memory().mem[address as Address]
+        } else if address == map::IE {
+            self.memory().mem[address as Address]
+        } else if map::NOT_USABLE2.contains(&address) {
+            self.memory().mem[address as Address]
+        } else if map::OAM.contains(&address) {
+            self.memory().mem[address as Address]
+        } else if map::NOT_USABLE1.contains(&address) {
+            self.memory().mem[(address - 0x2000) as Address]
+        } else {
+            //self.memory().mem[address as Address]
+            dbg!(address);
+            panic!();
         }
     }
 
@@ -137,8 +155,27 @@ impl Bus {
                 .cartridge
                 .borrow_mut()
                 .write(address, value);
-        } else {
+        } else if map::IO_REGISTERS.contains(&address) {
+            self.memory_mut().mem[address as Address] = value;
+        } else if map::VRAM.contains(&address) {
+            self.memory_mut().mem[address as Address] = value;
+        } else if map::HRAM.contains(&address) {
+            self.memory_mut().mem[address as Address] = value;
+        } else if map::WRAM.contains(&address) {
             self.memory_mut().mem[address as Address] = value;
+        } else if address == map::IE {
+            self.memory_mut().mem[address as Address] = value;
+        } else if map::NOT_USABLE2.contains(&address) {
+            self.memory_mut().mem[address as Address] = value;
+        } else if map::OAM.contains(&address) {
+            self.memory_mut().mem[address as Address] = value;
+        } else if map::NOT_USABLE1.contains(&address) {
+            self.memory_mut().mem[address - 0x2000 as Address] = value;
+        } else {
+            //self.memory_mut().mem[address as Address] = value;
+            dbg!(address);
+            dbg!(value);
+            panic!();
         }
     }
 
diff --git a/fpt/src/memory/map.rs b/fpt/src/memory/map.rs
index 6db6deb..3f3debc 100644
--- a/fpt/src/memory/map.rs
+++ b/fpt/src/memory/map.rs
@@ -38,6 +38,8 @@ pub const OAM: MemoryRange = 0xFE00..0xFEA0;
 /// Not usable https://gbdev.io/pandocs/Memory_Map.html#fea0-feff-range
 pub const NOT_USABLE2: MemoryRange = 0xFEA0..0xFF00;
 
+pub const IO_REGISTERS: MemoryRange = 0xFF00..0xFF80;
+
 //-------------------------------------------------------------------------
 // I/O Registers
 //-------------------------------------------------------------------------