diff --git a/mbc1.cpp b/mbc1.cpp
new file mode 100644
index 0000000..f90d1e1
--- /dev/null
+++ b/mbc1.cpp
@@ -0,0 +1,200 @@
+#include "mbc1.h"
+#include "mem.h"
+#include <stdlib.h>
+#include <SDL2/SDL.h>
+
+namespace mbc1
+{
+    #define ROM_BANK_SIZE 0x4000
+    #define RAM_BANK_SIZE 0x2000
+
+    uint8_t bootrom[256];
+    uint8_t *rom;
+    uint8_t vram[8192];
+    uint8_t exram[4 * RAM_BANK_SIZE];
+    uint8_t wram[8192];
+    uint8_t hram[512];
+
+    uint8_t tags[65536];
+
+    uint8_t current_rom_bank = 1;
+    uint8_t current_ram_bank = 0;
+    bool ram_enabled = false;
+    bool banking_mode = false; // false = ROM banking mode, true = RAM banking mode
+
+    uint8_t getKeypad(uint8_t value)
+    {
+        const uint8_t *keys = SDL_GetKeyboardState(NULL);
+        value = value & 0xf0;
+        if (value & 0x10) {
+            if (!keys[SDL_SCANCODE_RETURN]) value = value | 0x8;
+            if (!keys[SDL_SCANCODE_SPACE]) value = value | 0x4;
+            if (!keys[SDL_SCANCODE_Z]) value = value | 0x2;
+            if (!keys[SDL_SCANCODE_X]) value = value | 0x1;
+        } else if (value & 0x20) {
+            if (!keys[SDL_SCANCODE_DOWN]) value = value | 0x8;
+            if (!keys[SDL_SCANCODE_UP]) value = value | 0x4;
+            if (!keys[SDL_SCANCODE_LEFT]) value = value | 0x2;
+            if (!keys[SDL_SCANCODE_RIGHT]) value = value | 0x1;
+        } else {
+            value = value | 0x0f;
+        }
+        return value;
+    }
+
+    uint8_t readMem(uint16_t address)
+    {
+        if (address < 0x8000) {
+            if ( (address < 0x0100) && ((hram[0x150]&0x01)==0) ) return bootrom[address];
+            if (address < 0x4000) {
+                // ROM Bank 0
+                return rom[address];
+            } else {
+                // Switchable ROM bank
+                uint32_t banked_address = (current_rom_bank * ROM_BANK_SIZE) + (address - 0x4000);
+                return rom[banked_address];
+            }
+        } else if (address < 0xA000) {
+            return vram[address - 0x8000];
+        } else if (address < 0xC000) {
+            if (ram_enabled) {
+                uint32_t banked_address = (current_ram_bank * RAM_BANK_SIZE) + (address - 0xA000);
+                return exram[banked_address];
+            }
+            return 0xFF; // Return open bus value when RAM is disabled
+        } else if (address < 0xE000) {
+            return wram[address - 0xC000];
+        } else if (address < 0xFE00) {
+            return wram[address - 0xE000];
+        } else {
+            if (address==0xFF00) {
+                hram[address - 0XFE00] = getKeypad(hram[address - 0XFE00]);
+            }
+            return hram[address - 0XFE00];
+        }
+    }
+
+    void writeMem(uint16_t address, uint8_t value)
+    {
+        if (address < 0x8000) {
+            if (address < 0x2000) {
+                // Enable/disable RAM
+                ram_enabled = (value & 0x0F) == 0x0A;
+            } else if (address < 0x4000) {
+                // Select ROM bank
+                value &= 0x1F; // Lower 5 bits are used
+                if (value == 0) value = 1; // Bank 0 is not allowed
+                current_rom_bank = (current_rom_bank & 0x60) | value;
+            } else if (address < 0x6000) {
+                // Select RAM bank or upper bits of ROM bank
+                if (banking_mode) {
+                    current_ram_bank = value & 0x03; // 2 bits for RAM bank
+                } else {
+                    current_rom_bank = (current_rom_bank & 0x1F) | ((value & 0x03) << 5);
+                }
+            } else {
+                // Select banking mode
+                banking_mode = value & 0x01;
+            }
+        } else if (address < 0xA000) {
+            vram[address - 0x8000] = value;
+        } else if (address < 0xC000) {
+            if (ram_enabled) {
+                uint32_t banked_address = (current_ram_bank * RAM_BANK_SIZE) + (address - 0xA000);
+                exram[banked_address] = value;
+            }
+        } else if (address < 0xE000) {
+            wram[address - 0xC000] = value;
+        } else if (address < 0xFE00) {
+            wram[address - 0xE000] = value;
+        } else {
+            if ( (address==0xFF50) && ((value&0x01) != 1) ) return;  //Only allow disabling boot room
+            if ( (address==0xFF00) ) { value = value & 0x30; }
+            if ( (address==0xFF04) ) { hram[address-0xFE00] = 0; return; }
+            if ( (address==0xFF46) ) mem::init_dma_transfer(value);
+            hram[address - 0xFE00] = value;
+        }
+    }
+
+    uint8_t getTag(uint16_t address)
+    {
+        return tags[address];
+    }
+
+    void setTag(uint16_t address, uint8_t value)
+    {
+        tags[address] = value;
+    }
+
+    void saveState(FILE* f)
+    {
+
+    }
+
+    void loadState(FILE *f)
+    {
+
+    }
+
+    uint8_t* rawPtr(uint16_t address)
+    {
+        if (address < 0x8000) {
+            if ( (address < 0x0100) && ((hram[0x150]&0x01)==0) ) return &bootrom[address];
+            if (address < 0x4000) {
+                // ROM Bank 0
+                return &rom[address];
+            } else {
+                // Switchable ROM bank
+                uint32_t banked_address = (current_rom_bank * ROM_BANK_SIZE) + (address - 0x4000);
+                return &rom[banked_address];
+            }
+        } else if (address < 0xA000) {
+            return &vram[address - 0x8000];
+        } else if (address < 0xC000) {
+            if (ram_enabled) {
+                uint32_t banked_address = (current_ram_bank * RAM_BANK_SIZE) + (address - 0xA000);
+                return &exram[banked_address];
+            }
+            return nullptr; // Return open bus value when RAM is disabled
+        } else if (address < 0xE000) {
+            return &wram[address - 0xC000];
+        } else if (address < 0xFE00) {
+            return &wram[address - 0xE000];
+        } else {
+            return &hram[address - 0XFE00];
+        }
+    }
+
+    void reset()
+    {
+        FILE *f = fopen("dmg_boot.bin", "rb");
+        if (!f) { printf("ABORTING: 'dmg_boot.bin' not found!\n"); exit(1); }
+        fseek(f, 0, SEEK_END);
+        const int size = ftell(f);
+        fseek(f, 0, SEEK_SET);
+        fread(bootrom, size, 1, f);
+        fclose(f);
+
+        for (int i=0; i<8192; ++i) { vram[i] = 0; }
+        for (int i=0; i<4*RAM_BANK_SIZE; ++i) { exram[i] = 0; }
+        for (int i=0; i<8192; ++i) { wram[i] = 0; }
+        for (int i=0; i<512; ++i) { hram[i] = 0; }
+        for (int i=0; i<65536; ++i) { tags[i] = MEMTAG_NONE; }
+    }
+
+    void init(uint8_t *rom, uint32_t rom_size, uint32_t ram_size)
+    {
+        mem::readMem = mbc1::readMem;
+        mem::writeMem = mbc1::writeMem;
+        mem::getTag = mbc1::getTag;
+        mem::setTag = mbc1::setTag;
+        mem::saveState = mbc1::saveState;
+        mem::loadState = mbc1::loadState;
+        mem::reset = mbc1::reset;
+        mem::rawPtr = mbc1::rawPtr;
+
+        mbc1::rom = rom;
+
+        reset();
+    }
+}
\ No newline at end of file
diff --git a/mbc1.h b/mbc1.h
new file mode 100644
index 0000000..8452049
--- /dev/null
+++ b/mbc1.h
@@ -0,0 +1,7 @@
+#pragma once
+#include <stdint.h>
+
+namespace mbc1
+{
+    void init(uint8_t *rom, uint32_t rom_size, uint32_t ram_size);
+}
diff --git a/mem.cpp b/mem.cpp
index dd38a65..9ce33e7 100644
--- a/mem.cpp
+++ b/mem.cpp
@@ -4,6 +4,7 @@
 #include <stdio.h>
 
 #include "mbc_none.h"
+#include "mbc1.h"
 namespace mem
 {
     void (*reset)(void);
@@ -39,6 +40,11 @@ namespace mem
             case 0x00:
                 mbc_none::init(rom, rom_size, ram_size);
                 break;
+            case 0x01:
+            case 0x02:
+            case 0x03:
+                mbc1::init(rom, rom_size, ram_size);
+                break;
         };
     }