diff --git a/CorgiDS/CorgiDS.pro b/CorgiDS/CorgiDS.pro
index a148e45..cc6063d 100644
--- a/CorgiDS/CorgiDS.pro
+++ b/CorgiDS/CorgiDS.pro
@@ -46,7 +46,9 @@ SOURCES += \
     ../src/bios.cpp \
     ../src/qt/audiodevice.cpp \
     ../src/disasm_thumb.cpp \
-    ../src/debugger.cpp
+    ../src/debugger.cpp \
+    ../src/slot2.cpp \
+    ../src/gba/gbarw.cpp
 
 DEFINES += QT_DEPRECATED_WARNINGS
 DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000
@@ -80,7 +82,8 @@ HEADERS += \
     ../src/qt/emuthread.hpp \
     ../src/bios.hpp \
     ../src/qt/audiodevice.hpp \
-    ../src/debugger.hpp
+    ../src/debugger.hpp \
+    ../src/slot2.hpp
 
 FORMS += \
     ../src/qt/configwindow.ui \
diff --git a/src/arm7rw.cpp b/src/arm7rw.cpp
index 80ce025..ceff9de 100644
--- a/src/arm7rw.cpp
+++ b/src/arm7rw.cpp
@@ -8,6 +8,9 @@
 
 uint32_t Emulator::arm7_read_word(uint32_t address)
 {
+    //TODO: bad hack.
+    if (gba_mode)
+        return gba_read_word(address);
     if (address >= MAIN_RAM_START && address < SHARED_WRAM_START)
         return *(uint32_t*)&main_RAM[address & MAIN_RAM_MASK];
     if (address >= ARM7_WRAM_START && address < IO_REGS_START)
@@ -77,8 +80,8 @@ uint32_t Emulator::arm7_read_word(uint32_t address)
     }
     if (address >= 0x06000000 && address < 0x07000000)
         return gpu.read_ARM7<uint32_t>(address);
-    if (address >= GBA_ROM_START)
-        return 0xFFFFFFFF;
+    if (address >= GBA_ROM_START && address < GBA_RAM_START)
+        return slot2.read<uint32_t>(address);
     printf("\n(7) Unrecognized word read from $%08X", address);
     //exit(2);
     return 0;
@@ -86,6 +89,9 @@ uint32_t Emulator::arm7_read_word(uint32_t address)
 
 uint16_t Emulator::arm7_read_halfword(uint32_t address)
 {
+    //TODO: bad hack.
+    if (gba_mode)
+        return gba_read_halfword(address);
     if (address < 0x4000)
     {
         if (arm7.get_PC() > 0x4000)
@@ -193,8 +199,8 @@ uint16_t Emulator::arm7_read_halfword(uint32_t address)
         return wifi.read(address);
     if (address >= 0x06000000 && address < 0x07000000)
         return gpu.read_ARM7<uint16_t>(address);
-    if (address >= GBA_ROM_START)
-        return 0xFFFF;
+    if (address >= GBA_ROM_START && address < GBA_RAM_START)
+        return slot2.read<uint16_t>(address);
     printf("\n(7) Unrecognized halfword read from $%08X", address);
     //exit(2);
     return 0;
@@ -202,6 +208,9 @@ uint16_t Emulator::arm7_read_halfword(uint32_t address)
 
 uint8_t Emulator::arm7_read_byte(uint32_t address)
 {
+    //TODO: bad hack.
+    if (gba_mode)
+        return gba_read_byte(address);
     if (address >= MAIN_RAM_START && address < SHARED_WRAM_START)
         return main_RAM[address & MAIN_RAM_MASK];
     if (address >= ARM7_WRAM_START && address < IO_REGS_START)
@@ -253,6 +262,8 @@ uint8_t Emulator::arm7_read_byte(uint32_t address)
     }
     if (address >= 0x04000400 && address < 0x04000500)
         return spu.read_channel_byte(address);
+    if (address >= GBA_ROM_START && address < GBA_RAM_START)
+        return slot2.read<uint8_t>(address);
     printf("\n(7) Unrecognized byte read from $%08X", address);
     //exit(2);
     return 0;
@@ -260,10 +271,11 @@ uint8_t Emulator::arm7_read_byte(uint32_t address)
 
 void Emulator::arm7_write_word(uint32_t address, uint32_t word)
 {
-    if (address == 0x027E0014)
+    //TODO: bad hack.
+    if (gba_mode)
     {
-        printf("\n(7) Write of $%08X to $%08X", word, address);
-        //exit(0);
+        gba_write_word(address, word);
+        return;
     }
     if (address >= MAIN_RAM_START && address < SHARED_WRAM_START)
     {
@@ -413,6 +425,12 @@ void Emulator::arm7_write_word(uint32_t address, uint32_t word)
 
 void Emulator::arm7_write_halfword(uint32_t address, uint16_t halfword)
 {
+    //TODO: bad hack.
+    if (gba_mode)
+    {
+        gba_write_halfword(address, halfword);
+        return;
+    }
     if (address >= MAIN_RAM_START && address < SHARED_WRAM_START)
     {
         *(uint16_t*)&main_RAM[address & MAIN_RAM_MASK] = halfword;
@@ -581,6 +599,12 @@ void Emulator::arm7_write_halfword(uint32_t address, uint16_t halfword)
 
 void Emulator::arm7_write_byte(uint32_t address, uint8_t byte)
 {
+    //TODO: bad hack.
+    if (gba_mode)
+    {
+        gba_write_byte(address, byte);
+        return;
+    }
     if (address >= MAIN_RAM_START && address < SHARED_WRAM_START)
     {
         main_RAM[address & MAIN_RAM_MASK] = byte;
@@ -639,6 +663,9 @@ void Emulator::arm7_write_byte(uint32_t address, uint8_t byte)
         case 0x04000301:
             switch (byte)
             {
+                case 0x40:
+                    start_gba_mode(true);
+                    break;
                 case 0x80:
                     arm7.halt();
                     /*printf("\nHalted ARM7");
diff --git a/src/arm9rw.cpp b/src/arm9rw.cpp
index 623758b..ceee055 100644
--- a/src/arm9rw.cpp
+++ b/src/arm9rw.cpp
@@ -154,8 +154,8 @@ uint32_t Emulator::arm9_read_word(uint32_t address)
         return gpu.read_lcdc<uint32_t>(address);
     if (address >= OAM_START && address < GBA_ROM_START)
         return gpu.read_OAM<uint32_t>(address);
-    if (address >= GBA_ROM_START)
-        return 0xFFFFFFFF;
+    if (address >= GBA_ROM_START && address < GBA_RAM_START)
+        return slot2.read<uint32_t>(address);
     //Ignore reads from NULL
     printf("\n(9) Unrecognized word read from $%08X", address);
     //exit(1);
@@ -321,8 +321,8 @@ uint16_t Emulator::arm9_read_halfword(uint32_t address)
         return gpu.read_objb<uint16_t>(address);
     if (address >= VRAM_LCDC_A && address < VRAM_LCDC_END)
         return gpu.read_lcdc<uint16_t>(address);
-    if (address >= GBA_ROM_START)
-        return 0xFFFF;
+    if (address >= GBA_ROM_START && address < GBA_RAM_START)
+        return slot2.read<uint16_t>(address);
     printf("\n(9) Unrecognized halfword read from $%08X", address);
     return 0;
     //exit(1);
@@ -398,8 +398,8 @@ uint8_t Emulator::arm9_read_byte(uint32_t address)
         return gpu.read_lcdc<uint8_t>(address);
     if (address >= OAM_START && address < GBA_ROM_START)
         return gpu.read_OAM<uint8_t>(address);
-    if (address >= GBA_ROM_START)
-        return 0xFF;
+    if (address >= GBA_ROM_START && address < GBA_RAM_START)
+        return slot2.read<uint8_t>(address);
     printf("\n(9) Unrecognized byte read from $%08X", address);
     //exit(1);
     return 0;
diff --git a/src/config.cpp b/src/config.cpp
index 6a054e7..9dccf6c 100644
--- a/src/config.cpp
+++ b/src/config.cpp
@@ -12,7 +12,9 @@ namespace Config
     std::string arm9_bios_path;
     std::string firmware_path;
     std::string savelist_path;
+    std::string gba_bios_path;
     bool direct_boot_enabled;
+    bool gba_direct_boot;
     bool pause_when_unfocused;
 
     bool bg_enable[4];
diff --git a/src/config.hpp b/src/config.hpp
index eb5c96f..ea6809c 100644
--- a/src/config.hpp
+++ b/src/config.hpp
@@ -14,7 +14,9 @@ namespace Config
     extern std::string arm9_bios_path;
     extern std::string firmware_path;
     extern std::string savelist_path;
+    extern std::string gba_bios_path;
     extern bool direct_boot_enabled;
+    extern bool gba_direct_boot;
     extern bool pause_when_unfocused;
 
     extern bool bg_enable[4];
diff --git a/src/emulator.cpp b/src/emulator.cpp
index de433c0..0028a7d 100644
--- a/src/emulator.cpp
+++ b/src/emulator.cpp
@@ -75,6 +75,7 @@ void Emulator::power_on()
 {
     for (int i = 0; i < 4; i++)
         Config::bg_enable[i] = true;
+    gba_mode = false;
     cycle_count = 0;
     arm9.power_on();
     arm7.power_on();
@@ -161,12 +162,22 @@ int Emulator::load_ROM(string ROM_file_name)
 
 void Emulator::load_bios7(uint8_t *bios)
 {
-    memcpy(arm7_bios, bios, 16384 * sizeof(uint8_t));
+    memcpy(arm7_bios, bios, BIOS7_SIZE);
 }
 
 void Emulator::load_bios9(uint8_t *bios)
 {
-    memcpy(arm9_bios, bios, 4096 * sizeof(uint8_t));
+    memcpy(arm9_bios, bios, BIOS9_SIZE);
+}
+
+void Emulator::load_bios_gba(uint8_t *bios)
+{
+    memcpy(gba_bios, bios, BIOS_GBA_SIZE);
+}
+
+void Emulator::load_slot2(uint8_t *data, uint64_t size)
+{
+    slot2.load_data(data, size);
 }
 
 void Emulator::load_firmware(uint8_t *firmware)
@@ -184,7 +195,7 @@ int Emulator::load_firmware()
         return 1;
     }
     
-    arm9_bios_file.read((char*)arm9_bios, 4096 * sizeof(uint8_t));
+    arm9_bios_file.read((char*)arm9_bios, BIOS9_SIZE);
     printf("ARM9 BIOS loaded successfully.\n");
     
     arm9_bios_file.close();
@@ -197,11 +208,23 @@ int Emulator::load_firmware()
         return 1;
     }
     
-    arm7_bios_file.read((char*)arm7_bios, 16384 * sizeof(uint8_t));
+    arm7_bios_file.read((char*)arm7_bios, BIOS7_SIZE);
     printf("ARM7 BIOS loaded successfully.\n");
     
     arm7_bios_file.close();
 
+    ifstream gba_bios_file(Config::gba_bios_path, ios::in | ios::binary);
+    if (!gba_bios_file.is_open())
+    {
+        printf("Warning: failed to load GBA BIOS\n");
+    }
+    else
+    {
+        gba_bios_file.read((char*)gba_bios, BIOS_GBA_SIZE);
+        gba_bios_file.close();
+        printf("GBA BIOS loaded successfully.\n");
+    }
+
     return spi.init(Config::firmware_path);
 }
 
@@ -312,6 +335,36 @@ void Emulator::run()
     cart.save_check();
 }
 
+void Emulator::run_gba()
+{
+    gpu.start_frame();
+    while (!gpu.is_frame_complete())
+    {
+        arm7.execute();
+    }
+}
+
+bool Emulator::is_gba()
+{
+    return gba_mode;
+}
+
+//Only use throw_exception when emulation has started
+void Emulator::start_gba_mode(bool throw_exception)
+{
+    gba_mode = true;
+    arm7.jp(0, true);
+    debug();
+    //Allocate VRAM C and D as 256 KB work RAM
+    gpu.set_VRAMCNT_C(0x82);
+    gpu.set_VRAMCNT_D(0x86);
+    if (throw_exception)
+    {
+        //Signal to the emulation thread that emulation has switched from NDS to GBA
+        throw "!";
+    }
+}
+
 uint64_t Emulator::get_timestamp()
 {
     return system_timestamp;
diff --git a/src/emulator.hpp b/src/emulator.hpp
index 112a8b4..9308b43 100644
--- a/src/emulator.hpp
+++ b/src/emulator.hpp
@@ -15,6 +15,7 @@
 #include "interrupts.hpp"
 #include "ipc.hpp"
 #include "rtc.hpp"
+#include "slot2.hpp"
 #include "spi.hpp"
 #include "spu.hpp"
 #include "timers.hpp"
@@ -75,16 +76,20 @@ class Emulator
         NDS_DMA dma;
         GPU gpu;
         RealTimeClock rtc;
+        Slot2Device slot2;
         SPI_Bus spi;
         SPU spu;
         NDS_Timing timers;
         WiFi wifi;
+
+        bool gba_mode;
     
         uint8_t main_RAM[1024 * 1024 * 4]; //4 MB
         uint8_t shared_WRAM[1024 * 32]; //32 KB
         uint8_t arm7_WRAM[1024 * 64]; //64 KB
         uint8_t arm9_bios[BIOS9_SIZE];
         uint8_t arm7_bios[BIOS7_SIZE];
+        uint8_t gba_bios[BIOS_GBA_SIZE];
 
         //Scheduling
         uint64_t system_timestamp;
@@ -136,9 +141,11 @@ class Emulator
         Emulator();
         int init();
         int load_firmware();
+        void load_bios_gba(uint8_t* bios);
         void load_bios7(uint8_t* bios);
         void load_bios9(uint8_t* bios);
         void load_firmware(uint8_t* firmware);
+        void load_slot2(uint8_t* data, uint64_t size);
         void load_save_database(std::string name);
         int load_ROM(std::string ROM_name);
 
@@ -149,8 +156,12 @@ class Emulator
         void direct_boot();
         void debug();
         void run();
+        void run_gba();
         bool requesting_interrupt(int cpu_id);
 
+        bool is_gba();
+        void start_gba_mode(bool throw_exception);
+
         uint64_t get_timestamp();
 
         void get_upper_frame(uint32_t* buffer);
@@ -188,6 +199,13 @@ class Emulator
         void arm7_write_word(uint32_t address, uint32_t word);
         void arm7_write_halfword(uint32_t address, uint16_t halfword);
         void arm7_write_byte(uint32_t address, uint8_t byte);
+
+        uint32_t gba_read_word(uint32_t address);
+        uint16_t gba_read_halfword(uint32_t address);
+        uint8_t gba_read_byte(uint32_t address);
+        void gba_write_word(uint32_t address, uint32_t word);
+        void gba_write_halfword(uint32_t address, uint16_t halfword);
+        void gba_write_byte(uint32_t address, uint8_t byte);
     
         void cart_copy_keybuffer(uint8_t* buffer);
         void cart_write_header(uint32_t address, uint16_t halfword);
diff --git a/src/gba/gbarw.cpp b/src/gba/gbarw.cpp
new file mode 100644
index 0000000..4c648b0
--- /dev/null
+++ b/src/gba/gbarw.cpp
@@ -0,0 +1,108 @@
+#include "../emulator.hpp"
+
+uint32_t Emulator::gba_read_word(uint32_t address)
+{
+    if (address < 0x4000)
+        return *(uint32_t*)&gba_bios[address];
+    if (address >= 0x02000000 && address < 0x02040000)
+        return gpu.read_ARM7<uint32_t>(address);
+    if (address >= 0x03000000 && address < 0x03008000)
+        return *(uint32_t*)&shared_WRAM[address & 0x7FFF];
+    if (address >= 0x08000000 && address < 0x0A000000)
+        return slot2.read<uint32_t>(address);
+    printf("\nUnrecognized read32 $%08X", address);
+    return 0;
+    //throw "[GBA_MEM] Unrecognized read32";
+}
+
+uint16_t Emulator::gba_read_halfword(uint32_t address)
+{
+    if (address < 0x4000)
+        return *(uint16_t*)&gba_bios[address];
+    if (address >= 0x02000000 && address < 0x02040000)
+        return gpu.read_ARM7<uint16_t>(address);
+    if (address >= 0x03000000 && address < 0x03008000)
+        return *(uint16_t*)&shared_WRAM[address & 0x7FFF];
+    if (address >= 0x08000000 && address < 0x0A000000)
+        return slot2.read<uint16_t>(address);
+    printf("\nUnrecognized read16 $%08X", address);
+    return 0;
+    //throw "[GBA_MEM] Unrecognized read16";
+}
+
+uint8_t Emulator::gba_read_byte(uint32_t address)
+{
+    if (address < 0x4000)
+        return gba_bios[address];
+    if (address >= 0x02000000 && address < 0x02040000)
+        return gpu.read_ARM7<uint8_t>(address);
+    if (address >= 0x03000000 && address < 0x03008000)
+        return shared_WRAM[address & 0x7FFF];
+    if (address >= 0x08000000 && address < 0x0A000000)
+        return slot2.read<uint8_t>(address);
+    switch (address)
+    {
+        case 0x04000300:
+            return POSTFLG7;
+    }
+    printf("\nUnrecognized read8 $%08X", address);
+    return 0;
+    //throw "[GBA_MEM] Unrecognized read8";
+}
+
+void Emulator::gba_write_word(uint32_t address, uint32_t word)
+{
+    if (address >= 0x02000000 && address < 0x02040000)
+    {
+        gpu.write_ARM7<uint32_t>(address + 0x04000000, word);
+        return;
+    }
+    if (address >= 0x03000000 && address < 0x03008000)
+    {
+        *(uint32_t*)&shared_WRAM[address & 0x7FFF] = word;
+        return;
+    }
+    printf("\nUnrecognized write32 $%08X $%08X", address, word);
+    //throw "[GBA_MEM] Unrecognized write32";
+}
+
+void Emulator::gba_write_halfword(uint32_t address, uint16_t halfword)
+{
+    if (address >= 0x02000000 && address < 0x02040000)
+    {
+        gpu.write_ARM7<uint16_t>(address + 0x04000000, halfword);
+        return;
+    }
+    if (address >= 0x03000000 && address < 0x03008000)
+    {
+        *(uint16_t*)&shared_WRAM[address & 0x7FFF] = halfword;
+        return;
+    }
+    printf("\nUnrecognized write16 $%08X $%04X", address, halfword);
+    //throw "[GBA_MEM] Unrecognized write16";
+}
+
+void Emulator::gba_write_byte(uint32_t address, uint8_t byte)
+{
+    if (address >= 0x02000000 && address < 0x02040000)
+    {
+        gpu.write_ARM7<uint8_t>(address + 0x04000000, byte);
+        return;
+    }
+    if (address >= 0x03000000 && address < 0x03008000)
+    {
+        shared_WRAM[address & 0x7FFF] = byte;
+        return;
+    }
+    switch (address)
+    {
+        case 0x04000208:
+            int7_reg.IME = byte & 0x1;
+            return;
+        case 0x04000300:
+            POSTFLG7 = byte & 0x1;
+            return;
+    }
+    printf("\nUnrecognized write8 $%08X $%02X", address, byte);
+    //throw "[GBA_MEM] Unrecognized write8";
+}
diff --git a/src/memconsts.h b/src/memconsts.h
index 4ca5b91..14b282f 100644
--- a/src/memconsts.h
+++ b/src/memconsts.h
@@ -49,6 +49,7 @@
 #define VRAM_I_SIZE             1024 * 16
 #define BIOS9_SIZE              1024 * 4
 #define BIOS7_SIZE              1024 * 16
+#define BIOS_GBA_SIZE           1024 * 16
 
 //Masks
 #define ITCM_MASK               0x7FFF
diff --git a/src/qt/configwindow.cpp b/src/qt/configwindow.cpp
index 27fc456..13b2de5 100644
--- a/src/qt/configwindow.cpp
+++ b/src/qt/configwindow.cpp
@@ -19,6 +19,7 @@ ConfigWindow::ConfigWindow(QWidget *parent) :
     ui->arm9_BIOS_name->setReadOnly(true);
     ui->firmware_name->setReadOnly(true);
     ui->savelist_name->setReadOnly(true);
+    ui->gba_BIOS_name->setReadOnly(true);
 
     setWindowTitle("Emulator Configuration");
 
@@ -26,10 +27,14 @@ ConfigWindow::ConfigWindow(QWidget *parent) :
     Config::arm9_bios_path = cfg.value("boot/bios9path").toString().toStdString();
     Config::firmware_path = cfg.value("boot/firmwarepath").toString().toStdString();
     Config::savelist_path = cfg.value("saves/savelistpath").toString().toStdString();
+    Config::gba_bios_path = cfg.value("boot/gbapath").toString().toStdString();
 
     Config::direct_boot_enabled = cfg.value("boot/directboot").toBool();
     ui->toggle_direct_boot->setChecked(Config::direct_boot_enabled);
 
+    Config::gba_direct_boot = cfg.value("boot/gbadirectboot").toBool();
+    ui->toggle_gba_boot->setChecked(Config::gba_direct_boot);
+
     Config::pause_when_unfocused = false;
 
     update_ui();
@@ -84,7 +89,11 @@ void ConfigWindow::update_ui()
     QString save_path(Config::savelist_path.c_str());
     ui->savelist_name->setText(QFileInfo(save_path).fileName());
 
+    QString gba_path(Config::gba_bios_path.c_str());
+    ui->gba_BIOS_name->setText(QFileInfo(gba_path).fileName());
+
     ui->toggle_direct_boot->setChecked(Config::direct_boot_enabled);
+    ui->toggle_gba_boot->setChecked(Config::gba_direct_boot);
 }
 
 void ConfigWindow::on_find_savelist_clicked()
@@ -94,3 +103,17 @@ void ConfigWindow::on_find_savelist_clicked()
     cfg.setValue("saves/savelistpath", path);
     update_ui();
 }
+
+void ConfigWindow::on_find_gba_BIOS_clicked()
+{
+    QString path = QFileDialog::getOpenFileName(this, tr("Load GBA BIOS"), "", "GBA BIOS (*.bin *.rom)");
+    Config::gba_bios_path = path.toStdString();
+    cfg.setValue("boot/gbapath", path);
+    update_ui();
+}
+
+void ConfigWindow::on_toggle_gba_boot_clicked(bool checked)
+{
+    Config::gba_direct_boot = checked;
+    cfg.setValue("boot/gbadirectboot", checked);
+}
diff --git a/src/qt/configwindow.hpp b/src/qt/configwindow.hpp
index 7db4a72..719edd2 100644
--- a/src/qt/configwindow.hpp
+++ b/src/qt/configwindow.hpp
@@ -33,6 +33,10 @@ class ConfigWindow : public QWidget
 
         void on_find_savelist_clicked();
 
+        void on_find_gba_BIOS_clicked();
+
+        void on_toggle_gba_boot_clicked(bool checked);
+
 private:
         QSettings cfg;
         Ui::ConfigWindow *ui;
diff --git a/src/qt/configwindow.ui b/src/qt/configwindow.ui
index 5eda1e1..8d588ad 100644
--- a/src/qt/configwindow.ui
+++ b/src/qt/configwindow.ui
@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>360</width>
-    <height>210</height>
+    <height>274</height>
    </rect>
   </property>
   <property name="windowTitle">
@@ -17,57 +17,73 @@
    <property name="geometry">
     <rect>
      <x>10</x>
-     <y>170</y>
-     <width>291</width>
+     <y>210</y>
+     <width>331</width>
      <height>20</height>
     </rect>
    </property>
    <property name="text">
-    <string>Directly boot game ROM</string>
+    <string>Directly boot NDS games (skip boot-up)</string>
    </property>
   </widget>
-  <widget class="QWidget" name="gridLayoutWidget">
+  <widget class="QCheckBox" name="toggle_gba_boot">
    <property name="geometry">
     <rect>
      <x>10</x>
-     <y>0</y>
-     <width>341</width>
-     <height>161</height>
+     <y>240</y>
+     <width>331</width>
+     <height>20</height>
+    </rect>
+   </property>
+   <property name="text">
+    <string>Autoboot GBA games (starts upon loading ROM)</string>
+   </property>
+  </widget>
+  <widget class="QWidget" name="">
+   <property name="geometry">
+    <rect>
+     <x>10</x>
+     <y>10</y>
+     <width>330</width>
+     <height>191</height>
     </rect>
    </property>
    <layout class="QGridLayout" name="gridLayout">
-    <item row="1" column="0">
-     <widget class="QLabel" name="label_2">
+    <item row="0" column="0">
+     <widget class="QLabel" name="label_1">
       <property name="text">
        <string>ARM7 BIOS file:</string>
       </property>
      </widget>
     </item>
-    <item row="4" column="1">
-     <widget class="QLineEdit" name="savelist_name">
-      <property name="readOnly">
-       <bool>true</bool>
+    <item row="0" column="1">
+     <widget class="QLineEdit" name="arm7_BIOS_name"/>
+    </item>
+    <item row="0" column="2">
+     <widget class="QPushButton" name="find_arm7_BIOS">
+      <property name="text">
+       <string>Browse...</string>
       </property>
      </widget>
     </item>
-    <item row="3" column="1">
-     <widget class="QLineEdit" name="firmware_name"/>
-    </item>
-    <item row="4" column="0">
-     <widget class="QLabel" name="label_4">
+    <item row="1" column="0">
+     <widget class="QLabel" name="label_2">
       <property name="text">
-       <string>Savelist file:</string>
+       <string>ARM9 BIOS file:</string>
       </property>
      </widget>
     </item>
-    <item row="2" column="0">
-     <widget class="QLabel" name="label">
+    <item row="1" column="1">
+     <widget class="QLineEdit" name="arm9_BIOS_name"/>
+    </item>
+    <item row="1" column="2">
+     <widget class="QPushButton" name="find_arm9_BIOS">
       <property name="text">
-       <string>ARM9 BIOS file:</string>
+       <string>Browse...</string>
       </property>
      </widget>
     </item>
-    <item row="3" column="0">
+    <item row="2" column="0">
      <widget class="QLabel" name="label_3">
       <property name="text">
        <string>Firmware file:</string>
@@ -75,34 +91,52 @@
      </widget>
     </item>
     <item row="2" column="1">
-     <widget class="QLineEdit" name="arm9_BIOS_name"/>
-    </item>
-    <item row="1" column="1">
-     <widget class="QLineEdit" name="arm7_BIOS_name"/>
+     <widget class="QLineEdit" name="firmware_name"/>
     </item>
-    <item row="1" column="2">
-     <widget class="QPushButton" name="find_arm7_BIOS">
+    <item row="2" column="2">
+     <widget class="QPushButton" name="find_firmware">
       <property name="text">
        <string>Browse...</string>
       </property>
      </widget>
     </item>
-    <item row="2" column="2">
-     <widget class="QPushButton" name="find_arm9_BIOS">
+    <item row="3" column="0">
+     <widget class="QLabel" name="label_4">
       <property name="text">
-       <string>Browse...</string>
+       <string>Savelist file:</string>
+      </property>
+     </widget>
+    </item>
+    <item row="3" column="1">
+     <widget class="QLineEdit" name="savelist_name">
+      <property name="readOnly">
+       <bool>true</bool>
       </property>
      </widget>
     </item>
     <item row="3" column="2">
-     <widget class="QPushButton" name="find_firmware">
+     <widget class="QPushButton" name="find_savelist">
       <property name="text">
        <string>Browse...</string>
       </property>
      </widget>
     </item>
+    <item row="4" column="0">
+     <widget class="QLabel" name="label_5">
+      <property name="text">
+       <string>GBA BIOS file:</string>
+      </property>
+     </widget>
+    </item>
+    <item row="4" column="1">
+     <widget class="QLineEdit" name="gba_BIOS_name">
+      <property name="readOnly">
+       <bool>true</bool>
+      </property>
+     </widget>
+    </item>
     <item row="4" column="2">
-     <widget class="QPushButton" name="find_savelist">
+     <widget class="QPushButton" name="find_gba_BIOS">
       <property name="text">
        <string>Browse...</string>
       </property>
diff --git a/src/qt/emuthread.cpp b/src/qt/emuthread.cpp
index ae45306..f6875da 100644
--- a/src/qt/emuthread.cpp
+++ b/src/qt/emuthread.cpp
@@ -44,6 +44,19 @@ int EmuThread::load_game(QString ROM_name)
     return error;
 }
 
+void EmuThread::load_slot2(uint8_t* data, uint64_t size)
+{
+    load_mutex.lock();
+    e.load_slot2(data, size);
+    if (Config::gba_direct_boot)
+    {
+        e.power_on();
+        e.start_gba_mode(false);
+        unpause(GAME_NOT_STARTED);
+    }
+    load_mutex.unlock();
+}
+
 Emulator* EmuThread::get_emulator()
 {
     return &e;
@@ -75,12 +88,18 @@ void EmuThread::run()
             auto last_update = chrono::system_clock::now();
             try
             {
-                e.run();
+                if (e.is_gba())
+                    e.run_gba();
+                else
+                    e.run();
             }
             catch (const char* error)
             {
-                pause(GAME_NOT_STARTED);
-                emit emulation_error(error);
+                if (error[0] != '!')
+                {
+                    pause(GAME_NOT_STARTED);
+                    emit emulation_error(error);
+                }
             }
             frames++;
             e.get_upper_frame(upper_buffer);
diff --git a/src/qt/emuthread.hpp b/src/qt/emuthread.hpp
index 330bcea..576f17e 100644
--- a/src/qt/emuthread.hpp
+++ b/src/qt/emuthread.hpp
@@ -49,6 +49,7 @@ class EmuThread : public QThread
         int init();
         int load_firmware();
         void load_save_database();
+        void load_slot2(uint8_t* data, uint64_t size);
         int load_game(QString ROM_file);
 
         Emulator* get_emulator();
diff --git a/src/qt/emuwindow.cpp b/src/qt/emuwindow.cpp
index d384f7b..64087db 100644
--- a/src/qt/emuwindow.cpp
+++ b/src/qt/emuwindow.cpp
@@ -4,6 +4,8 @@
     See LICENSE.txt for details
 */
 
+#include <fstream>
+
 #include <QCoreApplication>
 #include <QCursor>
 #include <QFileDialog>
@@ -14,6 +16,8 @@
 #include "../config.hpp"
 #include "emuwindow.hpp"
 
+using namespace std;
+
 EmuWindow::EmuWindow(QWidget *parent) : QMainWindow(parent)
 {
 
@@ -21,6 +25,7 @@ EmuWindow::EmuWindow(QWidget *parent) : QMainWindow(parent)
 
 int EmuWindow::initialize()
 {
+    e = emuthread.get_emulator();
     if (emuthread.init())
         return 1;
 
@@ -32,12 +37,16 @@ int EmuWindow::initialize()
     load_ROM_act->setShortcuts(QKeySequence::Open);
     connect(load_ROM_act, &QAction::triggered, this, &EmuWindow::load_ROM);
 
+    //load_GBA_ROM_act = new QAction(tr("&Load GBA ROM..."), this);
+    //connect(load_GBA_ROM_act, &QAction::triggered, this, &EmuWindow::load_GBA_ROM);
+
     screenshot_act = new QAction(tr("&Save Screenshot As..."), this);
     screenshot_act->setShortcut(Qt::Key_F2);
     connect(screenshot_act, &QAction::triggered, this, &EmuWindow::screenshot);
 
     file_menu = menuBar()->addMenu(tr("&File"));
     file_menu->addAction(load_ROM_act);
+    //file_menu->addAction(load_GBA_ROM_act);
     file_menu->addAction(screenshot_act);
 
     config_act = new QAction(tr("&Config"), this);
@@ -63,7 +72,7 @@ int EmuWindow::initialize()
     setWindowTitle("CorgiDS");
     show();
 
-    spu_audio.set_SPU(emuthread.get_emulator()->get_SPU());
+    spu_audio.set_SPU(e->get_SPU());
     spu_audio.open(QIODevice::ReadOnly);
 
     //Initialize audio
@@ -296,7 +305,7 @@ void EmuWindow::load_ROM()
 {
     audio->stop();
     emuthread.pause(PAUSE_EVENT::LOADING_ROM);
-    if (emuthread.load_firmware())
+    if (e->load_firmware())
     {
         QMessageBox::critical(this, "Error", "Please load the BIOS and firmware images before "
                               "loading a game ROM.");
@@ -323,6 +332,44 @@ void EmuWindow::load_ROM()
     audio->start(&spu_audio);
 }
 
+void EmuWindow::load_GBA_ROM()
+{
+    audio->stop();
+    emuthread.pause(PAUSE_EVENT::LOADING_ROM);
+    //Load BIOS
+    ifstream bios_file(Config::gba_bios_path, ios::binary);
+    if (!bios_file.is_open())
+    {
+        QMessageBox::critical(this, "Error", "Please load the GBA BIOS image before "
+                              "loading a GBA ROM.");
+        emuthread.unpause(PAUSE_EVENT::LOADING_ROM);
+        return;
+    }
+    uint8_t* BIOS = new uint8_t[BIOS_GBA_SIZE];
+    bios_file.read((char*)BIOS, BIOS_GBA_SIZE);
+    bios_file.close();
+    e->load_bios_gba(BIOS);
+    delete[] BIOS;
+    QString name = QFileDialog::getOpenFileName(this, tr("Load GBA ROM"), "", "GBA ROMs (*.gba)");
+    if (name.length())
+    {
+        ifstream file(name.toStdString(), ios::binary | ios::ate);
+        if (file.is_open())
+        {
+            uint64_t ROM_size = file.tellg();
+            file.seekg(0, ios::beg);
+            uint8_t* data = new uint8_t[ROM_size];
+            file.read((char*)data, ROM_size);
+            file.close();
+            emuthread.load_slot2(data, ROM_size);
+            delete[] data;
+            printf("Slot 2 successfully loaded.");
+        }
+    }
+    audio->start(&spu_audio);
+    emuthread.unpause(PAUSE_EVENT::LOADING_ROM);
+}
+
 void EmuWindow::about()
 {
     QMessageBox::about(this, "CorgiDS v0.1", "Created by PSISP.");
diff --git a/src/qt/emuwindow.hpp b/src/qt/emuwindow.hpp
index 38c4db9..51f9501 100644
--- a/src/qt/emuwindow.hpp
+++ b/src/qt/emuwindow.hpp
@@ -24,6 +24,7 @@ class EmuWindow : public QMainWindow
 {
     Q_OBJECT
     private:
+        Emulator* e;
         EmuThread emuthread;
 
         AudioDevice spu_audio;
@@ -35,6 +36,7 @@ class EmuWindow : public QMainWindow
         QString ROM_file_name;
         QMenu* file_menu;
         QAction* load_ROM_act;
+        QAction* load_GBA_ROM_act;
         QAction* screenshot_act;
 
         QMenu* emulation_menu;
@@ -74,6 +76,7 @@ class EmuWindow : public QMainWindow
     private slots:
         void about();
         void load_ROM();
+        void load_GBA_ROM();
         void preferences();
         void screenshot();
         void handle_audio_state(QAudio::State);
diff --git a/src/slot2.cpp b/src/slot2.cpp
new file mode 100644
index 0000000..6d8089d
--- /dev/null
+++ b/src/slot2.cpp
@@ -0,0 +1,25 @@
+#include <cstring>
+#include "slot2.hpp"
+
+Slot2Device::Slot2Device() : memory(nullptr), mem_size(0)
+{
+
+}
+
+Slot2Device::~Slot2Device()
+{
+    if (memory)
+        delete[] memory;
+}
+
+void Slot2Device::load_data(uint8_t *data, uint64_t size)
+{
+    if (size)
+    {
+        if (memory)
+            delete[] memory;
+        memory = new uint8_t[size];
+        memcpy(memory, data, size);
+        mem_size = size;
+    }
+}
diff --git a/src/slot2.hpp b/src/slot2.hpp
new file mode 100644
index 0000000..c4b353a
--- /dev/null
+++ b/src/slot2.hpp
@@ -0,0 +1,30 @@
+#ifndef SLOT2_HPP
+#define SLOT2_HPP
+#include <cstdint>
+
+class Slot2Device
+{
+    private:
+        uint8_t* memory;
+        uint64_t mem_size;
+    public:
+        Slot2Device();
+        ~Slot2Device();
+
+        void load_data(uint8_t* data, uint64_t size);
+        template <typename T> T read(uint32_t address);
+        //template <typename T> void write(uint32_t address, T value);
+};
+
+template <typename T>
+T Slot2Device::read(uint32_t address)
+{
+    address &= 0x1FFFFFF;
+    if (address < mem_size)
+    {
+        return *(T*)&memory[address];
+    }
+    return (T)0xFFFFFFFF;
+}
+
+#endif // SLOT2_HPP