diff --git a/src/ARM.cpp b/src/ARM.cpp
index 2d8c8077..68cac59a 100644
--- a/src/ARM.cpp
+++ b/src/ARM.cpp
@@ -18,6 +18,7 @@
 
 #include <stdio.h>
 #include "NDS.h"
+#include "DSi.h"
 #include "ARM.h"
 #include "ARMInterpreter.h"
 #include "AREngine.h"
@@ -101,10 +102,55 @@ void ARM::Reset()
 
 void ARMv5::Reset()
 {
+    if (NDS::ConsoleType == 1)
+    {
+        BusRead8 = DSi::ARM9Read8;
+        BusRead16 = DSi::ARM9Read16;
+        BusRead32 = DSi::ARM9Read32;
+        BusWrite8 = DSi::ARM9Write8;
+        BusWrite16 = DSi::ARM9Write16;
+        BusWrite32 = DSi::ARM9Write32;
+        GetMemRegion = DSi::ARM9GetMemRegion;
+    }
+    else
+    {
+        BusRead8 = NDS::ARM9Read8;
+        BusRead16 = NDS::ARM9Read16;
+        BusRead32 = NDS::ARM9Read32;
+        BusWrite8 = NDS::ARM9Write8;
+        BusWrite16 = NDS::ARM9Write16;
+        BusWrite32 = NDS::ARM9Write32;
+        GetMemRegion = NDS::ARM9GetMemRegion;
+    }
+
     CP15Reset();
     ARM::Reset();
 }
 
+void ARMv4::Reset()
+{
+    if (NDS::ConsoleType)
+    {
+        BusRead8 = DSi::ARM7Read8;
+        BusRead16 = DSi::ARM7Read16;
+        BusRead32 = DSi::ARM7Read32;
+        BusWrite8 = DSi::ARM7Write8;
+        BusWrite16 = DSi::ARM7Write16;
+        BusWrite32 = DSi::ARM7Write32;
+    }
+    else
+    {
+        BusRead8 = NDS::ARM7Read8;
+        BusRead16 = NDS::ARM7Read16;
+        BusRead32 = NDS::ARM7Read32;
+        BusWrite8 = NDS::ARM7Write8;
+        BusWrite16 = NDS::ARM7Write16;
+        BusWrite32 = NDS::ARM7Write32;
+    }
+
+    ARM::Reset();
+}
+
 
 void ARM::DoSavestate(Savestate* file)
 {
diff --git a/src/ARM.h b/src/ARM.h
index 95c41d46..e0832e2a 100644
--- a/src/ARM.h
+++ b/src/ARM.h
@@ -23,7 +23,6 @@
 
 #include "types.h"
 #include "NDS.h"
-#include "DSi.h"
 
 #define ROR(x, n) (((x) >> (n)) | ((x) << (32-(n))))
 
@@ -133,6 +132,14 @@ public:
     NDS::MemRegion CodeMem;
 
     static u32 ConditionTable[16];
+
+protected:
+    u8 (*BusRead8)(u32 addr);
+    u16 (*BusRead16)(u32 addr);
+    u32 (*BusRead32)(u32 addr);
+    void (*BusWrite8)(u32 addr, u8 val);
+    void (*BusWrite16)(u32 addr, u16 val);
+    void (*BusWrite32)(u32 addr, u32 val);
 };
 
 class ARMv5 : public ARM
@@ -260,6 +267,8 @@ public:
 
     s32 RegionCodeCycles;
     u8* CurICacheLine;
+
+    bool (*GetMemRegion)(u32 addr, bool write, NDS::MemRegion* region);
 };
 
 class ARMv4 : public ARM
@@ -267,26 +276,25 @@ class ARMv4 : public ARM
 public:
     ARMv4();
 
+    void Reset();
+
     void JumpTo(u32 addr, bool restorecpsr = false);
 
     void Execute();
 
     u16 CodeRead16(u32 addr)
     {
-        //return NDS::ARM7Read16(addr);
-        return DSi::ARM7Read16(addr);
+        return BusRead16(addr);
     }
 
     u32 CodeRead32(u32 addr)
     {
-        //return NDS::ARM7Read32(addr);
-        return DSi::ARM7Read32(addr);
+        return BusRead32(addr);
     }
 
     void DataRead8(u32 addr, u32* val)
     {
-        *val = DSi::ARM7Read8(addr);
-        //*val = NDS::ARM7Read8(addr);
+        *val = BusRead8(addr);
         DataRegion = addr >> 24;
         DataCycles = NDS::ARM7MemTimings[DataRegion][0];
     }
@@ -295,8 +303,7 @@ public:
     {
         addr &= ~1;
 
-        *val = DSi::ARM7Read16(addr);
-        //*val = NDS::ARM7Read16(addr);
+        *val = BusRead16(addr);
         DataRegion = addr >> 24;
         DataCycles = NDS::ARM7MemTimings[DataRegion][0];
     }
@@ -305,8 +312,7 @@ public:
     {
         addr &= ~3;
 
-        *val = DSi::ARM7Read32(addr);
-        //*val = NDS::ARM7Read32(addr);
+        *val = BusRead32(addr);
         DataRegion = addr >> 24;
         DataCycles = NDS::ARM7MemTimings[DataRegion][2];
     }
@@ -315,15 +321,13 @@ public:
     {
         addr &= ~3;
 
-        *val = DSi::ARM7Read32(addr);
-        //*val = NDS::ARM7Read32(addr);
+        *val = BusRead32(addr);
         DataCycles += NDS::ARM7MemTimings[DataRegion][3];
     }
 
     void DataWrite8(u32 addr, u8 val)
     {
-        DSi::ARM7Write8(addr, val);
-        //NDS::ARM7Write8(addr, val);
+        BusWrite8(addr, val);
         DataRegion = addr >> 24;
         DataCycles = NDS::ARM7MemTimings[DataRegion][0];
     }
@@ -332,8 +336,7 @@ public:
     {
         addr &= ~1;
 
-        DSi::ARM7Write16(addr, val);
-        //NDS::ARM7Write16(addr, val);
+        BusWrite16(addr, val);
         DataRegion = addr >> 24;
         DataCycles = NDS::ARM7MemTimings[DataRegion][0];
     }
@@ -342,8 +345,7 @@ public:
     {
         addr &= ~3;
 
-        DSi::ARM7Write32(addr, val);
-        //NDS::ARM7Write32(addr, val);
+        BusWrite32(addr, val);
         DataRegion = addr >> 24;
         DataCycles = NDS::ARM7MemTimings[DataRegion][2];
     }
@@ -352,8 +354,7 @@ public:
     {
         addr &= ~3;
 
-        DSi::ARM7Write32(addr, val);
-        //NDS::ARM7Write32(addr, val);
+        BusWrite32(addr, val);
         DataCycles += NDS::ARM7MemTimings[DataRegion][3];
     }
 
diff --git a/src/CP15.cpp b/src/CP15.cpp
index b61cc458..d340b9e5 100644
--- a/src/CP15.cpp
+++ b/src/CP15.cpp
@@ -720,8 +720,7 @@ u32 ARMv5::CodeRead32(u32 addr, bool branch)
 
     if (CodeMem.Mem) return *(u32*)&CodeMem.Mem[addr & CodeMem.Mask];
 
-    //return NDS::ARM9Read32(addr);
-    return DSi::ARM9Read32(addr);
+    return BusRead32(addr);
 }
 
 
@@ -740,8 +739,7 @@ void ARMv5::DataRead8(u32 addr, u32* val)
         return;
     }
 
-    *val = DSi::ARM9Read8(addr);
-    //*val = NDS::ARM9Read8(addr);
+    *val = BusRead8(addr);
     DataCycles = MemTimings[addr >> 12][1];
 }
 
@@ -762,8 +760,7 @@ void ARMv5::DataRead16(u32 addr, u32* val)
         return;
     }
 
-    *val = DSi::ARM9Read16(addr);
-    //*val = NDS::ARM9Read16(addr);
+    *val = BusRead16(addr);
     DataCycles = MemTimings[addr >> 12][1];
 }
 
@@ -784,8 +781,7 @@ void ARMv5::DataRead32(u32 addr, u32* val)
         return;
     }
 
-    *val = DSi::ARM9Read32(addr);
-    //*val = NDS::ARM9Read32(addr);
+    *val = BusRead32(addr);
     DataCycles = MemTimings[addr >> 12][2];
 }
 
@@ -806,8 +802,7 @@ void ARMv5::DataRead32S(u32 addr, u32* val)
         return;
     }
 
-    *val = DSi::ARM9Read32(addr);
-    //*val = NDS::ARM9Read32(addr);
+    *val = BusRead32(addr);
     DataCycles += MemTimings[addr >> 12][3];
 }
 
@@ -826,8 +821,7 @@ void ARMv5::DataWrite8(u32 addr, u8 val)
         return;
     }
 
-    DSi::ARM9Write8(addr, val);
-    //NDS::ARM9Write8(addr, val);
+    BusWrite8(addr, val);
     DataCycles = MemTimings[addr >> 12][1];
 }
 
@@ -848,8 +842,7 @@ void ARMv5::DataWrite16(u32 addr, u16 val)
         return;
     }
 
-    DSi::ARM9Write16(addr, val);
-    //NDS::ARM9Write16(addr, val);
+    BusWrite16(addr, val);
     DataCycles = MemTimings[addr >> 12][1];
 }
 
@@ -870,8 +863,7 @@ void ARMv5::DataWrite32(u32 addr, u32 val)
         return;
     }
 
-    DSi::ARM9Write32(addr, val);
-    //NDS::ARM9Write32(addr, val);
+    BusWrite32(addr, val);
     DataCycles = MemTimings[addr >> 12][2];
 }
 
@@ -892,8 +884,7 @@ void ARMv5::DataWrite32S(u32 addr, u32 val)
         return;
     }
 
-    DSi::ARM9Write32(addr, val);
-    //NDS::ARM9Write32(addr, val);
+    BusWrite32(addr, val);
     DataCycles += MemTimings[addr >> 12][3];
 }
 
@@ -906,7 +897,6 @@ void ARMv5::GetCodeMemRegion(u32 addr, NDS::MemRegion* region)
         return;
     }*/
 
-    DSi::ARM9GetMemRegion(addr, false, &CodeMem);
-    //NDS::ARM9GetMemRegion(addr, false, &CodeMem);
+    GetMemRegion(addr, false, &CodeMem);
 }
 
diff --git a/src/DMA.cpp b/src/DMA.cpp
index 8e294fc4..cd2df459 100644
--- a/src/DMA.cpp
+++ b/src/DMA.cpp
@@ -53,8 +53,6 @@ DMA::DMA(u32 cpu, u32 num)
         CountMask = 0x001FFFFF;
     else
         CountMask = (num==3 ? 0x0000FFFF : 0x00003FFF);
-
-    Reset();
 }
 
 DMA::~DMA()
@@ -77,6 +75,21 @@ void DMA::Reset()
 
     Running = false;
     InProgress = false;
+
+    if (NDS::ConsoleType == 1)
+    {
+        BusRead16 = (CPU==0) ? DSi::ARM9Read16 : DSi::ARM7Read16;
+        BusRead32 = (CPU==0) ? DSi::ARM9Read32 : DSi::ARM7Read32;
+        BusWrite16 = (CPU==0) ? DSi::ARM9Write16 : DSi::ARM7Write16;
+        BusWrite32 = (CPU==0) ? DSi::ARM9Write32 : DSi::ARM7Write32;
+    }
+    else
+    {
+        BusRead16 = (CPU==0) ? NDS::ARM9Read16 : NDS::ARM7Read16;
+        BusRead32 = (CPU==0) ? NDS::ARM9Read32 : NDS::ARM7Read32;
+        BusWrite16 = (CPU==0) ? NDS::ARM9Write16 : NDS::ARM7Write16;
+        BusWrite32 = (CPU==0) ? NDS::ARM9Write32 : NDS::ARM7Write32;
+    }
 }
 
 void DMA::DoSavestate(Savestate* file)
@@ -227,8 +240,7 @@ void DMA::Run9()
         {
             NDS::ARM9Timestamp += (unitcycles << NDS::ARM9ClockShift);
 
-            //NDS::ARM9Write16(CurDstAddr, NDS::ARM9Read16(CurSrcAddr));
-            DSi::ARM9Write16(CurDstAddr, DSi::ARM9Read16(CurSrcAddr));
+            BusWrite16(CurDstAddr, BusRead16(CurSrcAddr));
 
             CurSrcAddr += SrcAddrInc<<1;
             CurDstAddr += DstAddrInc<<1;
@@ -264,8 +276,7 @@ void DMA::Run9()
         {
             NDS::ARM9Timestamp += (unitcycles << NDS::ARM9ClockShift);
 
-            //NDS::ARM9Write32(CurDstAddr, NDS::ARM9Read32(CurSrcAddr));
-            DSi::ARM9Write32(CurDstAddr, DSi::ARM9Read32(CurSrcAddr));
+            BusWrite32(CurDstAddr, BusRead32(CurSrcAddr));
 
             CurSrcAddr += SrcAddrInc<<2;
             CurDstAddr += DstAddrInc<<2;
@@ -341,8 +352,7 @@ void DMA::Run7()
         {
             NDS::ARM7Timestamp += unitcycles;
 
-            //NDS::ARM7Write16(CurDstAddr, NDS::ARM7Read16(CurSrcAddr));
-            DSi::ARM7Write16(CurDstAddr, DSi::ARM7Read16(CurSrcAddr));
+            BusWrite16(CurDstAddr, BusRead16(CurSrcAddr));
 
             CurSrcAddr += SrcAddrInc<<1;
             CurDstAddr += DstAddrInc<<1;
@@ -378,8 +388,7 @@ void DMA::Run7()
         {
             NDS::ARM7Timestamp += unitcycles;
 
-            //NDS::ARM7Write32(CurDstAddr, NDS::ARM7Read32(CurSrcAddr));
-            DSi::ARM7Write32(CurDstAddr, DSi::ARM7Read32(CurSrcAddr));
+            BusWrite32(CurDstAddr, BusRead32(CurSrcAddr));
 
             CurSrcAddr += SrcAddrInc<<2;
             CurDstAddr += DstAddrInc<<2;
diff --git a/src/DMA.h b/src/DMA.h
index 2e7678cb..0344fbac 100644
--- a/src/DMA.h
+++ b/src/DMA.h
@@ -86,6 +86,11 @@ private:
     bool Stall;
 
     bool IsGXFIFODMA;
+
+    u16 (*BusRead16)(u32 addr);
+    u32 (*BusRead32)(u32 addr);
+    void (*BusWrite16)(u32 addr, u16 val);
+    void (*BusWrite32)(u32 addr, u32 val);
 };
 
 #endif
diff --git a/src/DSi.cpp b/src/DSi.cpp
index 58f39c2a..520b269c 100644
--- a/src/DSi.cpp
+++ b/src/DSi.cpp
@@ -18,6 +18,7 @@
 
 #include <stdio.h>
 #include <string.h>
+#include "Config.h"
 #include "NDS.h"
 #include "DSi.h"
 #include "ARM.h"
@@ -221,7 +222,7 @@ bool LoadBIOS()
     memset(ARM9iBIOS, 0, 0x10000);
     memset(ARM7iBIOS, 0, 0x10000);
 
-    f = Platform::OpenLocalFile("bios9i.bin", "rb");
+    f = Platform::OpenLocalFile(Config::DSiBIOS9Path, "rb");
     if (!f)
     {
         printf("ARM9i BIOS not found\n");
@@ -238,7 +239,7 @@ bool LoadBIOS()
         fclose(f);
     }
 
-    f = Platform::OpenLocalFile("bios7i.bin", "rb");
+    f = Platform::OpenLocalFile(Config::DSiBIOS7Path, "rb");
     if (!f)
     {
         printf("ARM7i BIOS not found\n");
@@ -283,7 +284,7 @@ bool LoadNAND()
     memset(NWRAMEnd, 0, sizeof(NWRAMEnd));
     memset(NWRAMMask, 0, sizeof(NWRAMMask));
 
-    FILE* f = Platform::OpenLocalFile("nand.bin", "rb");
+    FILE* f = Platform::OpenLocalFile(Config::DSiNANDPath, "rb");
     if (f)
     {
         u32 bootparams[8];
diff --git a/src/NDS.cpp b/src/NDS.cpp
index 001dfe6d..22368aef 100644
--- a/src/NDS.cpp
+++ b/src/NDS.cpp
@@ -62,6 +62,8 @@ namespace NDS
 //
 // timings for GBA slot and wifi are set up at runtime
 
+int ConsoleType;
+
 u8 ARM9MemTimings[0x40000][4];
 u8 ARM7MemTimings[0x20000][4];
 
@@ -296,6 +298,8 @@ void InitTimings()
     // TODO: +3c nonseq waitstate doesn't apply to DMA!
     // but of course mainRAM always gets 8c nonseq waitstate
 
+    // TODO: DSi-specific timings!!
+
     SetARM9RegionTimings(0x00000000, 0xFFFFFFFF, 32, 1 + 3, 1); // void
 
     SetARM9RegionTimings(0xFFFF0000, 0xFFFFFFFF, 32, 1 + 3, 1); // BIOS
@@ -321,6 +325,12 @@ void InitTimings()
 
 void SetupDirectBoot()
 {
+    if (ConsoleType == 1)
+    {
+        printf("!! DIRECT BOOT NOT SUPPORTED IN DSI MODE\n");
+        return;
+    }
+
     u32 bootparams[8];
     memcpy(bootparams, &NDSCart::CartROM[0x20], 8*4);
 
@@ -469,7 +479,7 @@ void Reset()
         fclose(f);
     }
 
-    if (true)
+    if (ConsoleType == 1)
     {
         DSi::LoadBIOS();
         DSi::LoadNAND();
@@ -559,8 +569,11 @@ void Reset()
     RTC::Reset();
     Wifi::Reset();
 
-    DSi::Reset();
-    KeyInput &= ~(1 << (16+6)); // TODO
+    if (ConsoleType == 1)
+    {
+        DSi::Reset();
+        KeyInput &= ~(1 << (16+6));
+    }
 
     AREngine::Reset();
 }
@@ -670,6 +683,11 @@ bool DoSavestate(Savestate* file)
 {
     file->Section("NDSG");
 
+    // TODO:
+    // * do something for bool's (sizeof=1)
+    // * do something for 'loading DSi-mode savestate in DS mode' and vice-versa
+    // * add IE2/IF2 there
+
     file->VarArray(MainRAM, 0x400000);
     file->VarArray(SharedWRAM, 0x8000);
     file->VarArray(ARM7WRAM, 0x10000);
@@ -772,6 +790,11 @@ bool DoSavestate(Savestate* file)
     return true;
 }
 
+void SetConsoleType(int type)
+{
+    ConsoleType = type;
+}
+
 bool LoadROM(const char* path, const char* sram, bool direct)
 {
     if (NDSCart::LoadROM(path, sram, direct))
@@ -883,7 +906,7 @@ u32 RunFrame()
             if (!(CPUStop & 0x80000000)) DMAs[1]->Run();
             if (!(CPUStop & 0x80000000)) DMAs[2]->Run();
             if (!(CPUStop & 0x80000000)) DMAs[3]->Run();
-            DSi::RunNDMAs(0);
+            if (ConsoleType == 1) DSi::RunNDMAs(0);
         }
         else
         {
@@ -906,7 +929,7 @@ u32 RunFrame()
                 DMAs[5]->Run();
                 DMAs[6]->Run();
                 DMAs[7]->Run();
-                DSi::RunNDMAs(1);
+                if (ConsoleType == 1) DSi::RunNDMAs(1);
             }
             else
             {
@@ -990,7 +1013,7 @@ void CancelEvent(u32 id)
 
 void TouchScreen(u16 x, u16 y)
 {
-    if (true) // TODO!!
+    if (ConsoleType == 1)
     {
         DSi_SPI_TSC::SetTouchCoords(x, y);
     }
@@ -1003,7 +1026,7 @@ void TouchScreen(u16 x, u16 y)
 
 void ReleaseScreen()
 {
-    if (true) // TODO!!
+    if (ConsoleType == 1)
     {
         DSi_SPI_TSC::SetTouchCoords(0x000, 0xFFF);
     }
@@ -1144,7 +1167,8 @@ void UpdateIRQ(u32 cpu)
     if (IME[cpu] & 0x1)
     {
         arm->IRQ = IE[cpu] & IF[cpu];
-        if (cpu) arm->IRQ |= (IE2 & IF2);
+        if ((ConsoleType == 1) && cpu)
+            arm->IRQ |= (IE2 & IF2);
     }
     else
     {
@@ -1223,7 +1247,7 @@ void GXFIFOStall()
         DMAs[1]->StallIfRunning();
         DMAs[2]->StallIfRunning();
         DMAs[3]->StallIfRunning();
-        DSi::StallNDMAs();
+        if (ConsoleType == 1) DSi::StallNDMAs();
     }
 }
 
@@ -1361,6 +1385,7 @@ void NocashPrint(u32 ncpu, u32 addr)
 void MonitorARM9Jump(u32 addr)
 {
     // checkme: can the entrypoint addr be THUMB?
+    // also TODO: make it work in DSi mode
 
     if ((!RunningGame) && NDSCart::CartROM)
     {
@@ -1468,7 +1493,7 @@ bool DMAsInMode(u32 cpu, u32 mode)
     if (DMAs[cpu+2]->IsInMode(mode)) return true;
     if (DMAs[cpu+3]->IsInMode(mode)) return true;
 
-    if (true)
+    if (ConsoleType == 1)
     {
         cpu >>= 2;
         return DSi::NDMAsInMode(cpu, NDMAModes[mode]);
@@ -1484,7 +1509,10 @@ bool DMAsRunning(u32 cpu)
     if (DMAs[cpu+1]->IsRunning()) return true;
     if (DMAs[cpu+2]->IsRunning()) return true;
     if (DMAs[cpu+3]->IsRunning()) return true;
-    if (DSi::NDMAsRunning(cpu>>2)) return true;
+    if (ConsoleType == 1)
+    {
+        if (DSi::NDMAsRunning(cpu>>2)) return true;
+    }
     return false;
 }
 
@@ -1496,7 +1524,7 @@ void CheckDMAs(u32 cpu, u32 mode)
     DMAs[cpu+2]->StartIfNeeded(mode);
     DMAs[cpu+3]->StartIfNeeded(mode);
 
-    if (true)
+    if (ConsoleType == 1)
     {
         cpu >>= 2;
         DSi::CheckNDMAs(cpu, NDMAModes[mode]);
@@ -1511,7 +1539,7 @@ void StopDMAs(u32 cpu, u32 mode)
     DMAs[cpu+2]->StopIfNeeded(mode);
     DMAs[cpu+3]->StopIfNeeded(mode);
 
-    if (true)
+    if (ConsoleType == 1)
     {
         cpu >>= 2;
         DSi::StopNDMAs(cpu, NDMAModes[mode]);
diff --git a/src/NDS.h b/src/NDS.h
index 26931de3..9c5fe3dd 100644
--- a/src/NDS.h
+++ b/src/NDS.h
@@ -133,6 +133,8 @@ typedef struct
 
 } MemRegion;
 
+extern int ConsoleType;
+
 extern u8 ARM9MemTimings[0x40000][4];
 extern u8 ARM7MemTimings[0x20000][4];
 
@@ -174,6 +176,9 @@ bool DoSavestate(Savestate* file);
 void SetARM9RegionTimings(u32 addrstart, u32 addrend, int buswidth, int nonseq, int seq);
 void SetARM7RegionTimings(u32 addrstart, u32 addrend, int buswidth, int nonseq, int seq);
 
+// 0=DS  1=DSi
+void SetConsoleType(int type);
+
 bool LoadROM(const char* path, const char* sram, bool direct);
 bool LoadGBAROM(const char* path, const char* sram);
 void LoadBIOS();
diff --git a/src/NDSCart.cpp b/src/NDSCart.cpp
index 9497d33c..b326dd69 100644
--- a/src/NDSCart.cpp
+++ b/src/NDSCart.cpp
@@ -561,11 +561,18 @@ void Key1_ApplyKeycode(u32* keycode, u32 mod)
 
 void Key1_InitKeycode(bool dsi, u32 idcode, u32 level, u32 mod)
 {
-    //memcpy(Key1_KeyBuf, &NDS::ARM7BIOS[0x30], 0x1048); // hax
-    if (dsi)
-        memcpy(Key1_KeyBuf, &DSi::ARM7Init[0x254], 0x1048); // hax
+    // TODO: source the key data from different possible places
+    if (NDS::ConsoleType == 1)
+    {
+        if (dsi)
+            memcpy(Key1_KeyBuf, &DSi::ARM7Init[0x254], 0x1048); // hax
+        else
+            memcpy(Key1_KeyBuf, &DSi::ITCMInit[0x4894], 0x1048); // hax
+    }
     else
-        memcpy(Key1_KeyBuf, &DSi::ITCMInit[0x4894], 0x1048); // hax
+    {
+        memcpy(Key1_KeyBuf, &NDS::ARM7BIOS[0x30], 0x1048); // hax
+    }
 
     u32 keycode[3] = {idcode, idcode>>1, idcode<<1};
     if (level >= 1) Key1_ApplyKeycode(keycode, mod);
diff --git a/src/SPI.cpp b/src/SPI.cpp
index 29f33212..ac407073 100644
--- a/src/SPI.cpp
+++ b/src/SPI.cpp
@@ -93,7 +93,10 @@ void Reset()
     if (Firmware) delete[] Firmware;
     Firmware = NULL;
 
-    strncpy(FirmwarePath, Config::FirmwarePath, 1023);
+    if (NDS::ConsoleType == 1)
+        strncpy(FirmwarePath, Config::DSiFirmwarePath, 1023);
+    else
+        strncpy(FirmwarePath, Config::FirmwarePath, 1023);
 
     FILE* f = Platform::OpenLocalFile(FirmwarePath, "rb");
     if (!f)
@@ -620,7 +623,7 @@ void Reset()
     SPI_Firmware::Reset();
     SPI_Powerman::Reset();
     SPI_TSC::Reset();
-    DSi_SPI_TSC::Reset();
+    if (NDS::ConsoleType == 1) DSi_SPI_TSC::Reset();
 }
 
 void DoSavestate(Savestate* file)
@@ -633,7 +636,7 @@ void DoSavestate(Savestate* file)
     SPI_Firmware::DoSavestate(file);
     SPI_Powerman::DoSavestate(file);
     SPI_TSC::DoSavestate(file);
-    DSi_SPI_TSC::DoSavestate(file);
+    if (NDS::ConsoleType == 1) DSi_SPI_TSC::DoSavestate(file);
 }
 
 
@@ -647,8 +650,12 @@ void WriteCnt(u16 val)
         {
         case 0x0000: SPI_Powerman::Hold = 0; break;
         case 0x0100: SPI_Firmware::Hold = 0; break;
-        //case 0x0200: SPI_TSC::DataPos = 0; break;
-        case 0x0200: DSi_SPI_TSC::DataPos = 0; break;
+        case 0x0200:
+            if (NDS::ConsoleType == 1)
+                DSi_SPI_TSC::DataPos = 0;
+            else
+                SPI_TSC::DataPos = 0;
+            break;
         }
     }
 
@@ -674,8 +681,11 @@ u8 ReadData()
     {
     case 0x0000: return SPI_Powerman::Read();
     case 0x0100: return SPI_Firmware::Read();
-    //case 0x0200: return SPI_TSC::Read();
-    case 0x0200: return DSi_SPI_TSC::Read();
+    case 0x0200:
+        if (NDS::ConsoleType == 1)
+            return DSi_SPI_TSC::Read();
+        else
+            return SPI_TSC::Read();
     default: return 0;
     }
 }
@@ -691,8 +701,12 @@ void WriteData(u8 val)
     {
     case 0x0000: SPI_Powerman::Write(val, Cnt&(1<<11)); break;
     case 0x0100: SPI_Firmware::Write(val, Cnt&(1<<11)); break;
-    //case 0x0200: SPI_TSC::Write(val, Cnt&(1<<11)); break;
-    case 0x0200: DSi_SPI_TSC::Write(val, Cnt&(1<<11)); break;
+    case 0x0200:
+        if (NDS::ConsoleType == 1)
+            DSi_SPI_TSC::Write(val, Cnt&(1<<11));
+        else
+            SPI_TSC::Write(val, Cnt&(1<<11));
+        break;
     default: printf("SPI to unknown device %04X %02X\n", Cnt, val); break;
     }
 
diff --git a/src/SPU.cpp b/src/SPU.cpp
index 959de128..9f6b1072 100644
--- a/src/SPU.cpp
+++ b/src/SPU.cpp
@@ -155,6 +155,11 @@ Channel::~Channel()
 
 void Channel::Reset()
 {
+    if (NDS::ConsoleType == 1)
+        BusRead32 = DSi::ARM7Read32;
+    else
+        BusRead32 = NDS::ARM7Read32;
+
     SetCnt(0);
     SrcAddr = 0;
     TimerReload = 0;
@@ -217,8 +222,7 @@ void Channel::FIFO_BufferData()
 
     for (u32 i = 0; i < burstlen; i += 4)
     {
-        //FIFO[FIFOWritePos] = NDS::ARM7Read32(SrcAddr + FIFOReadOffset);
-        FIFO[FIFOWritePos] = DSi::ARM7Read32(SrcAddr + FIFOReadOffset);
+        FIFO[FIFOWritePos] = BusRead32(SrcAddr + FIFOReadOffset);
         FIFOReadOffset += 4;
         FIFOWritePos++;
         FIFOWritePos &= 0x7;
@@ -466,6 +470,11 @@ CaptureUnit::~CaptureUnit()
 
 void CaptureUnit::Reset()
 {
+    if (NDS::ConsoleType == 1)
+        BusWrite32 = DSi::ARM7Write32;
+    else
+        BusWrite32 = NDS::ARM7Write32;
+
     SetCnt(0);
     DstAddr = 0;
     TimerReload = 0;
@@ -501,8 +510,7 @@ void CaptureUnit::FIFO_FlushData()
 {
     for (u32 i = 0; i < 4; i++)
     {
-        //NDS::ARM7Write32(DstAddr + FIFOWriteOffset, FIFO[FIFOReadPos]);
-        DSi::ARM7Write32(DstAddr + FIFOWriteOffset, FIFO[FIFOReadPos]);
+        BusWrite32(DstAddr + FIFOWriteOffset, FIFO[FIFOReadPos]);
 
         FIFOReadPos++;
         FIFOReadPos &= 0x3;
diff --git a/src/SPU.h b/src/SPU.h
index 74a44710..8ab17a03 100644
--- a/src/SPU.h
+++ b/src/SPU.h
@@ -142,6 +142,9 @@ public:
     }
 
     void PanOutput(s32* inbuf, u32 samples, s32* leftbuf, s32* rightbuf);
+
+private:
+    u32 (*BusRead32)(u32 addr);
 };
 
 class CaptureUnit
@@ -196,6 +199,9 @@ public:
     }
 
     void Run(s32 sample);
+
+private:
+    void (*BusWrite32)(u32 addr, u32 val);
 };
 
 }
diff --git a/src/frontend/FrontendUtil.h b/src/frontend/FrontendUtil.h
index 6b83cbc8..099583fb 100644
--- a/src/frontend/FrontendUtil.h
+++ b/src/frontend/FrontendUtil.h
@@ -46,6 +46,15 @@ enum
     Load_FirmwareBad,
     Load_FirmwareNotBootable,
 
+    Load_DSiBIOS9Missing,
+    Load_DSiBIOS9Bad,
+
+    Load_DSiBIOS7Missing,
+    Load_DSiBIOS7Bad,
+
+    Load_DSiNANDMissing,
+    Load_DSiNANDBad,
+
     // TODO: more precise errors for ROM loading
     Load_ROMLoadError,
 };
diff --git a/src/frontend/Util_ROM.cpp b/src/frontend/Util_ROM.cpp
index d4105509..8116a932 100644
--- a/src/frontend/Util_ROM.cpp
+++ b/src/frontend/Util_ROM.cpp
@@ -96,6 +96,42 @@ int VerifyDSBIOS()
     return Load_OK;
 }
 
+int VerifyDSiBIOS()
+{
+    FILE* f;
+    long len;
+
+    // TODO: check the first 32 bytes
+
+    f = Platform::OpenLocalFile(Config::DSiBIOS9Path, "rb");
+    if (!f) return Load_DSiBIOS9Missing;
+
+    fseek(f, 0, SEEK_END);
+    len = ftell(f);
+    if (len != 0x10000)
+    {
+        fclose(f);
+        return Load_DSiBIOS9Bad;
+    }
+
+    fclose(f);
+
+    f = Platform::OpenLocalFile(Config::DSiBIOS7Path, "rb");
+    if (!f) return Load_DSiBIOS7Missing;
+
+    fseek(f, 0, SEEK_END);
+    len = ftell(f);
+    if (len != 0x10000)
+    {
+        fclose(f);
+        return Load_DSiBIOS7Bad;
+    }
+
+    fclose(f);
+
+    return Load_OK;
+}
+
 int VerifyDSFirmware()
 {
     FILE* f;
@@ -110,7 +146,6 @@ int VerifyDSFirmware()
     {
         // 128KB firmware, not bootable
         fclose(f);
-        return Load_OK; // FIXME!!!!
         return Load_FirmwareNotBootable;
     }
     else if (len != 0x40000 && len != 0x80000)
@@ -124,6 +159,45 @@ int VerifyDSFirmware()
     return Load_OK;
 }
 
+int VerifyDSiFirmware()
+{
+    FILE* f;
+    long len;
+
+    f = Platform::OpenLocalFile(Config::DSiFirmwarePath, "rb");
+    if (!f) return Load_FirmwareMissing;
+
+    fseek(f, 0, SEEK_END);
+    len = ftell(f);
+    if (len != 0x20000)
+    {
+        // not 128KB
+        // TODO: check whether those work
+        fclose(f);
+        return Load_FirmwareBad;
+    }
+
+    fclose(f);
+
+    return Load_OK;
+}
+
+int VerifyDSiNAND()
+{
+    FILE* f;
+    long len;
+
+    f = Platform::OpenLocalFile(Config::DSiNANDPath, "rb");
+    if (!f) return Load_DSiNANDMissing;
+
+    // TODO: some basic checks
+    // check that it has the nocash footer, and all
+
+    fclose(f);
+
+    return Load_OK;
+}
+
 int LoadBIOS()
 {
     int res;
@@ -131,8 +205,22 @@ int LoadBIOS()
     res = VerifyDSBIOS();
     if (res != Load_OK) return res;
 
-    res = VerifyDSFirmware();
-    if (res != Load_OK) return res;
+    if (Config::ConsoleType == 1)
+    {
+        res = VerifyDSiBIOS();
+        if (res != Load_OK) return res;
+
+        res = VerifyDSiFirmware();
+        if (res != Load_OK) return res;
+
+        res = VerifyDSiNAND();
+        if (res != Load_OK) return res;
+    }
+    else
+    {
+        res = VerifyDSFirmware();
+        if (res != Load_OK) return res;
+    }
 
     // TODO:
     // original code in the libui frontend called NDS::LoadGBAROM() if needed
@@ -142,6 +230,7 @@ int LoadBIOS()
     ROMPath[ROMSlot_NDS][0] = '\0';
     SRAMPath[ROMSlot_NDS][0] = '\0';
 
+    NDS::SetConsoleType(Config::ConsoleType);
     NDS::LoadBIOS();
 
     SavestateLoaded = false;
@@ -154,16 +243,39 @@ int LoadROM(const char* file, int slot)
     int res;
     bool directboot = Config::DirectBoot != 0;
 
+    if (Config::ConsoleType == 1 && slot == 1)
+    {
+        // cannot load a GBA ROM into a DSi
+        return Load_ROMLoadError;
+    }
+
     res = VerifyDSBIOS();
     if (res != Load_OK) return res;
 
-    res = VerifyDSFirmware();
-    if (res != Load_OK)
+    if (Config::ConsoleType == 1)
     {
-        if (res == Load_FirmwareNotBootable)
-            directboot = true;
-        else
-            return res;
+        res = VerifyDSiBIOS();
+        if (res != Load_OK) return res;
+
+        res = VerifyDSiFirmware();
+        if (res != Load_OK) return res;
+
+        res = VerifyDSiNAND();
+        if (res != Load_OK) return res;
+
+        GBACart::Eject();
+        ROMPath[ROMSlot_GBA][0] = '\0';
+    }
+    else
+    {
+        res = VerifyDSFirmware();
+        if (res != Load_OK)
+        {
+            if (res == Load_FirmwareNotBootable)
+                directboot = true;
+            else
+                return res;
+        }
     }
 
     char oldpath[1024];
@@ -177,6 +289,8 @@ int LoadROM(const char* file, int slot)
     SetupSRAMPath(0);
     SetupSRAMPath(1);
 
+    NDS::SetConsoleType(Config::ConsoleType);
+
     if (slot == ROMSlot_NDS && NDS::LoadROM(ROMPath[slot], SRAMPath[slot], directboot))
     {
         SavestateLoaded = false;
@@ -225,17 +339,36 @@ int Reset()
     res = VerifyDSBIOS();
     if (res != Load_OK) return res;
 
-    res = VerifyDSFirmware();
-    if (res != Load_OK)
+    if (Config::ConsoleType == 1)
     {
-        if (res == Load_FirmwareNotBootable)
-            directboot = true;
-        else
-            return res;
+        res = VerifyDSiBIOS();
+        if (res != Load_OK) return res;
+
+        res = VerifyDSiFirmware();
+        if (res != Load_OK) return res;
+
+        res = VerifyDSiNAND();
+        if (res != Load_OK) return res;
+
+        GBACart::Eject();
+        ROMPath[ROMSlot_GBA][0] = '\0';
+    }
+    else
+    {
+        res = VerifyDSFirmware();
+        if (res != Load_OK)
+        {
+            if (res == Load_FirmwareNotBootable)
+                directboot = true;
+            else
+                return res;
+        }
     }
 
     SavestateLoaded = false;
 
+    NDS::SetConsoleType(Config::ConsoleType);
+
     if (ROMPath[ROMSlot_NDS][0] == '\0')
     {
         NDS::LoadBIOS();
diff --git a/src/frontend/qt_sdl/EmuSettingsDialog.cpp b/src/frontend/qt_sdl/EmuSettingsDialog.cpp
index 7760a88b..09faf4eb 100644
--- a/src/frontend/qt_sdl/EmuSettingsDialog.cpp
+++ b/src/frontend/qt_sdl/EmuSettingsDialog.cpp
@@ -49,7 +49,7 @@ EmuSettingsDialog::EmuSettingsDialog(QWidget* parent) : QDialog(parent), ui(new
     ui->txtDSiNANDPath->setText(Config::DSiNANDPath);
 
     ui->cbxConsoleType->addItem("DS");
-    ui->cbxConsoleType->addItem("DSi");
+    ui->cbxConsoleType->addItem("DSi (experimental)");
     ui->cbxConsoleType->setCurrentIndex(Config::ConsoleType);
 
     ui->chkDirectBoot->setChecked(Config::DirectBoot != 0);
diff --git a/src/frontend/qt_sdl/main.cpp b/src/frontend/qt_sdl/main.cpp
index ef21bc76..7b3d5cd2 100644
--- a/src/frontend/qt_sdl/main.cpp
+++ b/src/frontend/qt_sdl/main.cpp
@@ -1360,17 +1360,40 @@ QString MainWindow::loadErrorStr(int error)
 {
     switch (error)
     {
-    case Frontend::Load_BIOS9Missing: return "DS ARM9 BIOS was not found or could not be accessed. Check your emu settings.";
-    case Frontend::Load_BIOS9Bad:     return "DS ARM9 BIOS is not a valid BIOS dump.";
+    case Frontend::Load_BIOS9Missing:
+        return "DS ARM9 BIOS was not found or could not be accessed. Check your emu settings.";
+    case Frontend::Load_BIOS9Bad:
+        return "DS ARM9 BIOS is not a valid BIOS dump.";
 
-    case Frontend::Load_BIOS7Missing: return "DS ARM7 BIOS was not found or could not be accessed. Check your emu settings.";
-    case Frontend::Load_BIOS7Bad:     return "DS ARM7 BIOS is not a valid BIOS dump.";
+    case Frontend::Load_BIOS7Missing:
+        return "DS ARM7 BIOS was not found or could not be accessed. Check your emu settings.";
+    case Frontend::Load_BIOS7Bad:
+        return "DS ARM7 BIOS is not a valid BIOS dump.";
 
-    case Frontend::Load_FirmwareMissing:     return "DS firmware was not found or could not be accessed. Check your emu settings.";
-    case Frontend::Load_FirmwareBad:         return "DS firmware is not a valid firmware dump.";
-    case Frontend::Load_FirmwareNotBootable: return "DS firmware is not bootable.";
+    case Frontend::Load_FirmwareMissing:
+        return "DS firmware was not found or could not be accessed. Check your emu settings.";
+    case Frontend::Load_FirmwareBad:
+        return "DS firmware is not a valid firmware dump.";
+    case Frontend::Load_FirmwareNotBootable:
+        return "DS firmware is not bootable.";
 
-    case Frontend::Load_ROMLoadError: return "Failed to load the ROM. Make sure the file is accessible and isn't used by another application.";
+    case Frontend::Load_DSiBIOS9Missing:
+        return "DSi ARM9 BIOS was not found or could not be accessed. Check your emu settings.";
+    case Frontend::Load_DSiBIOS9Bad:
+        return "DSi ARM9 BIOS is not a valid BIOS dump.";
+
+    case Frontend::Load_DSiBIOS7Missing:
+        return "DSi ARM7 BIOS was not found or could not be accessed. Check your emu settings.";
+    case Frontend::Load_DSiBIOS7Bad:
+        return "DSi ARM7 BIOS is not a valid BIOS dump.";
+
+    case Frontend::Load_DSiNANDMissing:
+        return "DSi NAND was not found or could not be accessed. Check your emu settings.";
+    case Frontend::Load_DSiNANDBad:
+        return "DSi NAND is not a valid NAND dump.";
+
+    case Frontend::Load_ROMLoadError:
+        return "Failed to load the ROM. Make sure the file is accessible and isn't used by another application.";
 
     default: return "Unknown error during launch; smack Arisotura.";
     }