diff --git a/src/apu/bapu/core/bapugen.exe b/src/apu/bapu/core/bapugen.exe
deleted file mode 100644
index 745ee0e2..00000000
Binary files a/src/apu/bapu/core/bapugen.exe and /dev/null differ
diff --git a/src/base.h b/src/base.h
index 1b1bb63c..080a24d2 100644
--- a/src/base.h
+++ b/src/base.h
@@ -1,4 +1,4 @@
-#define BSNES_VERSION "0.015 rc3" //wip47
+#define BSNES_VERSION "0.016"
 #define BSNES_TITLE "bsnes v" BSNES_VERSION
 
 #define MEMCORE bMemBus
@@ -7,9 +7,6 @@
 #define DSPCORE bDSP
 #define PPUCORE bPPU
 
-//debugging extensions (~10% speed hit)
-#define DEBUGGER
-
 //game genie + pro action replay code support (~1-3% speed hit)
 #define CHEAT_SYSTEM
 
@@ -19,6 +16,9 @@
 //enable JMA support
 //#define JMA_SUPPORT
 
+//debugging extensions (~10% speed hit)
+#define DEBUGGER
+
 //snes core polymorphism
 //(allow mem/cpu/apu/ppu overriding, ~10% speed hit)
 //#define POLYMORPHISM
diff --git a/src/cart/cart.cpp b/src/cart/cart.cpp
index 23de454e..f2dcd936 100644
--- a/src/cart/cart.cpp
+++ b/src/cart/cart.cpp
@@ -93,10 +93,15 @@ int32 score_lo = 0,
 uint16 cksum, icksum;
   cksum  = rom[0x7fc0 +  CKSUM] | (rom[0x7fc0 +  CKSUM + 1] << 8);
   icksum = rom[0x7fc0 + ICKSUM] | (rom[0x7fc0 + ICKSUM + 1] << 8);
-  if((cksum + icksum) == 0xffff)score_lo += 8;
+  if((cksum + icksum) == 0xffff && (cksum != 0) && (icksum != 0)) {
+    score_lo += 8;
+  }
+
   cksum  = rom[0xffc0 +  CKSUM] | (rom[0xffc0 +  CKSUM + 1] << 8);
   icksum = rom[0xffc0 + ICKSUM] | (rom[0xffc0 + ICKSUM + 1] << 8);
-  if((cksum + icksum) == 0xffff)score_hi += 8;
+  if((cksum + icksum) == 0xffff && (cksum != 0) && (icksum != 0)) {
+    score_hi += 8;
+  }
 
   if(rom_size < 0x401000) {
     score_ex = 0;
diff --git a/src/cart/cart.h b/src/cart/cart.h
index fbd710b3..e0df6e40 100644
--- a/src/cart/cart.h
+++ b/src/cart/cart.h
@@ -57,6 +57,7 @@ struct {
   void save_sram();
   void find_header();
   void read_header();
+  bool loaded() { return cart_loaded; }
   bool load(const char *fn);
   bool unload();
 
diff --git a/src/cpu/bcpu/bcpu.cpp b/src/cpu/bcpu/bcpu.cpp
index ee855a4b..8d5dae8c 100644
--- a/src/cpu/bcpu/bcpu.cpp
+++ b/src/cpu/bcpu/bcpu.cpp
@@ -79,7 +79,9 @@ void bCPU::power() {
 
 void bCPU::reset() {
 //reset vector location
-  regs.pc  = r_mem->read(0xfffc) | (r_mem->read(0xfffd) << 8);
+  regs.pc.d = 0;
+  regs.pc.l = r_mem->read(0xfffc);
+  regs.pc.h = r_mem->read(0xfffd);
 
 //registers are not fully reset by SNES
   regs.x.h = 0x00;
@@ -91,6 +93,9 @@ void bCPU::reset() {
   regs.e   = 1;
   regs.mdr = 0x00;
 
+//simulate pbr:pc push during reset irq vector
+  regs.s.l -= 3;
+
   time_reset();
   mmio_reset();
   dma_reset();
diff --git a/src/cpu/bcpu/bcpu_exec.cpp b/src/cpu/bcpu/bcpu_exec.cpp
index cfc13322..3020aff9 100644
--- a/src/cpu/bcpu/bcpu_exec.cpp
+++ b/src/cpu/bcpu/bcpu_exec.cpp
@@ -1,5 +1,7 @@
 void bCPU::last_cycle() {
-  time.nmi_pending = nmi_test();
+//DMV27: keep previous nmi value,
+//to allow wai and irq to work properly
+  time.nmi_pending = nmi_test() || time.nmi_pending;
   time.irq_pending = irq_test();
 }
 
diff --git a/src/cpu/bcpu/bcpu_int.cpp b/src/cpu/bcpu/bcpu_int.cpp
index 88336745..d2ee6e5f 100644
--- a/src/cpu/bcpu/bcpu_int.cpp
+++ b/src/cpu/bcpu/bcpu_int.cpp
@@ -13,18 +13,37 @@ void bCPU::irq_run() {
 //WDC documentation is incorrect, first cycle
 //is a memory read fetch from PBR:PC
   switch(status.cycle_pos++) {
-  case 0: add_cycles(r_mem->speed(regs.pc.d));   break;
-  case 1: add_cycles(6);                         break;
-  case 2: stack_write(regs.pc.b);                break;
-  case 3: stack_write(regs.pc.h);                break;
-  case 4: stack_write(regs.pc.l);                break;
-  case 5: stack_write(regs.p);                   break;
-  case 6: rd.l = op_read(OPMODE_ADDR, aa.w);     break;
-  case 7: rd.h = op_read(OPMODE_ADDR, aa.w + 1);
+  case 0:
+  //read from PBR:PC, but do not increment PC counter
+    mem_read(regs.pc.d);
+    break;
+  case 1:
+    cpu_io();
+    if(regs.e)status.cycle_pos++;
+    break;
+  case 2:
+    stack_write(regs.pc.b);
+    break;
+  case 3:
+    stack_write(regs.pc.h);
+    break;
+  case 4:
+    stack_write(regs.pc.l);
+    break;
+  case 5:
+  //emulation-mode irqs clear brk bit 0x10
+    stack_write((regs.e) ? (regs.p & ~0x10) : regs.p);
+    break;
+  case 6:
+  //todo: test if NMI can override IRQ here...
+    rd.l = op_read(OPMODE_ADDR, aa.w);
     regs.pc.b = 0x00;
-    regs.pc.w = rd.w;
     regs.p.i  = 1;
     regs.p.d  = 0;
+    break;
+  case 7:
+    rd.h = op_read(OPMODE_ADDR, aa.w + 1);
+    regs.pc.w = rd.w;
   #ifdef DEBUGGER
   //let debugger know the new IRQ opcode address
     snes->notify(SNES::CPU_EXEC_OPCODE_END);
diff --git a/src/cpu/bcpu/bcpu_mmio.cpp b/src/cpu/bcpu/bcpu_mmio.cpp
index efc76b3f..d2a03a7c 100644
--- a/src/cpu/bcpu/bcpu_mmio.cpp
+++ b/src/cpu/bcpu/bcpu_mmio.cpp
@@ -17,16 +17,16 @@ void bCPU::mmio_reset() {
   status.pio = 0xff;
 
 //$4202-$4203
-  status.mul_a = 0x00;
-  status.mul_b = 0x00;
+  status.mul_a = 0xff;
+  status.mul_b = 0xff;
 
 //$4204-$4206
-  status.div_a = 0x0000;
-  status.div_b = 0x00;
+  status.div_a = 0xffff;
+  status.div_b = 0xff;
 
 //$4207-$420a
-  status.hirq_pos = 0;
-  status.virq_pos = 0;
+  status.hirq_pos = 0x01ff;
+  status.virq_pos = 0x01ff;
 
 //$4214-$4217
   status.r4214 = 0x0000;
@@ -505,7 +505,6 @@ void bCPU::mmio_w420a(uint8 value) {
 
 //DMAEN
 void bCPU::mmio_w420b(uint8 value) {
-int len;
   if(value != 0x00) {
     run_state.dma = true;
     status.dma_state = DMASTATE_DMASYNC;
diff --git a/src/cpu/bcpu/core/bcpugen.exe b/src/cpu/bcpu/core/bcpugen.exe
deleted file mode 100644
index 90c162f7..00000000
Binary files a/src/cpu/bcpu/core/bcpugen.exe and /dev/null differ
diff --git a/src/cpu/bcpu/core/op_misc.b b/src/cpu/bcpu/core/op_misc.b
index 7e8e07e3..b939dfeb 100644
--- a/src/cpu/bcpu/core/op_misc.b
+++ b/src/cpu/bcpu/core/op_misc.b
@@ -42,13 +42,13 @@ cop(0x02, 0xfff4, 0xfff5, 0xffe4, 0xffe5) {
 3:stack_write(regs.pc.h);
 4:stack_write(regs.pc.l);
 5:stack_write(regs.p);
-6:rd.l = op_read(OPMODE_LONG, (regs.e)?$1:$3);
-7:last_cycle();
-  rd.h = op_read(OPMODE_LONG, (regs.e)?$2:$4);
+6:rd.l = op_read(OPMODE_LONG, (regs.e) ? $1 : $3);
   regs.pc.b = 0x00;
-  regs.pc.w = rd.w;
   regs.p.i  = 1;
   regs.p.d  = 0;
+7:last_cycle();
+  rd.h = op_read(OPMODE_LONG, (regs.e) ? $2 : $4);
+  regs.pc.w = rd.w;
 }
 
 stp(0xdb) {
@@ -64,10 +64,16 @@ wai(0xcb) {
   run_state.wai = true;
 2:last_cycle();
   cpu_io();
-  if(run_state.wai) {
-  //this can be cleared within last_cycle()
-    regs.pc.w--;
-  }
+//no wakeup delay if last_cycle() cancelled wai
+  if(run_state.wai == false)end;
+3:last_cycle();
+  cpu_io();
+//sleep another i/o cycle
+//note: this should alert the debugger that wai is continuing...
+  if(run_state.wai == true)status.cycle_pos--;
+//wai wakeup delay (one i/o cycle)
+4:last_cycle();
+  cpu_io();
 }
 
 xce(0xfb) {
@@ -183,12 +189,8 @@ txs(0x9a) {
   cpu_io();
   if(regs.e) {
     regs.s.l = regs.x.l;
-    regs.p.n = !!(regs.s.l & 0x80);
-    regs.p.z = (regs.s.l == 0);
   } else {
     regs.s.w = regs.x.w;
-    regs.p.n = !!(regs.s.w & 0x8000);
-    regs.p.z = (regs.s.w == 0);
   }
 }
 
diff --git a/src/cpu/bcpu/core/op_misc.cpp b/src/cpu/bcpu/core/op_misc.cpp
index 0eb209c1..75c3b57b 100644
--- a/src/cpu/bcpu/core/op_misc.cpp
+++ b/src/cpu/bcpu/core/op_misc.cpp
@@ -113,15 +113,15 @@ void bCPU::op_brk() {
     stack_write(regs.p);
     } break;
   case 6: {
-    rd.l = op_read(OPMODE_LONG, (regs.e)?0xfffe:0xffe6);
+    rd.l = op_read(OPMODE_LONG, (regs.e) ? 0xfffe : 0xffe6);
+    regs.pc.b = 0x00;
+    regs.p.i  = 1;
+    regs.p.d  = 0;
     } break;
   case 7: {
     last_cycle();
-    rd.h = op_read(OPMODE_LONG, (regs.e)?0xffff:0xffe7);
-    regs.pc.b = 0x00;
+    rd.h = op_read(OPMODE_LONG, (regs.e) ? 0xffff : 0xffe7);
     regs.pc.w = rd.w;
-    regs.p.i  = 1;
-    regs.p.d  = 0;
     status.cycle_pos = 0;
     } break;
   }
@@ -146,15 +146,15 @@ void bCPU::op_cop() {
     stack_write(regs.p);
     } break;
   case 6: {
-    rd.l = op_read(OPMODE_LONG, (regs.e)?0xfff4:0xffe4);
+    rd.l = op_read(OPMODE_LONG, (regs.e) ? 0xfff4 : 0xffe4);
+    regs.pc.b = 0x00;
+    regs.p.i  = 1;
+    regs.p.d  = 0;
     } break;
   case 7: {
     last_cycle();
-    rd.h = op_read(OPMODE_LONG, (regs.e)?0xfff5:0xffe5);
-    regs.pc.b = 0x00;
+    rd.h = op_read(OPMODE_LONG, (regs.e) ? 0xfff5 : 0xffe5);
     regs.pc.w = rd.w;
-    regs.p.i  = 1;
-    regs.p.d  = 0;
     status.cycle_pos = 0;
     } break;
   }
@@ -184,10 +184,20 @@ void bCPU::op_wai() {
   case 2: {
     last_cycle();
     cpu_io();
-    if(run_state.wai) {
-    //this can be cleared within last_cycle()
-      regs.pc.w--;
-    }
+  //no wakeup delay if last_cycle() cancelled wai
+    if(run_state.wai == false)status.cycle_pos = 0;
+    } break;
+  case 3: {
+    last_cycle();
+    cpu_io();
+  //sleep another i/o cycle
+  //note: this should alert the debugger that wai is continuing...
+    if(run_state.wai == true)status.cycle_pos--;
+  //wai wakeup delay (one i/o cycle)
+    } break;
+  case 4: {
+    last_cycle();
+    cpu_io();
     status.cycle_pos = 0;
     } break;
   }
@@ -523,12 +533,8 @@ void bCPU::op_txs() {
     cpu_io();
     if(regs.e) {
       regs.s.l = regs.x.l;
-      regs.p.n = !!(regs.s.l & 0x80);
-      regs.p.z = (regs.s.l == 0);
     } else {
       regs.s.w = regs.x.w;
-      regs.p.n = !!(regs.s.w & 0x8000);
-      regs.p.z = (regs.s.w == 0);
     }
     status.cycle_pos = 0;
     } break;
diff --git a/src/cpu/bcpu/core/op_pc.b b/src/cpu/bcpu/core/op_pc.b
index e202f222..cad17d60 100644
--- a/src/cpu/bcpu/core/op_pc.b
+++ b/src/cpu/bcpu/core/op_pc.b
@@ -126,7 +126,8 @@ rti(0x40) {
     regs.y.h = 0x00;
   }
 4:rd.l = stack_read();
-5:rd.h = stack_read();
+5:if(regs.e)last_cycle();
+  rd.h = stack_read();
   if(regs.e) {
     regs.pc.w = rd.w;
     end;
diff --git a/src/cpu/bcpu/core/op_pc.cpp b/src/cpu/bcpu/core/op_pc.cpp
index 3a25945c..13f7bd9f 100644
--- a/src/cpu/bcpu/core/op_pc.cpp
+++ b/src/cpu/bcpu/core/op_pc.cpp
@@ -417,6 +417,7 @@ void bCPU::op_rti() {
     rd.l = stack_read();
     } break;
   case 5: {
+    if(regs.e)last_cycle();
     rd.h = stack_read();
     if(regs.e) {
       regs.pc.w = rd.w;
diff --git a/src/cpu/bcpu/dma/dma.cpp b/src/cpu/bcpu/dma/dma.cpp
index 4718e2bd..b7442b28 100644
--- a/src/cpu/bcpu/dma/dma.cpp
+++ b/src/cpu/bcpu/dma/dma.cpp
@@ -233,25 +233,31 @@ void bCPU::hdma_activate() {
 }
 
 void bCPU::dma_reset() {
+  status.dma_state        = DMASTATE_CPUSYNC;
+  status.hdma_state       = HDMASTATE_CPUSYNC;
+  status.dma_cycle_count  = 0;
+  status.hdma_cycle_count = 0;
+
   for(int i = 0; i < 8; i++) {
     channel[i].read_index        = 0;
     channel[i].active            = false;
     channel[i].hdma_enabled      = false;
-    channel[i].dmap              = 0x00;
-    channel[i].direction         = 0;
-    channel[i].hdma_indirect     = false;
-    channel[i].incmode           = 1;
-    channel[i].fixedxfer         = false;
-    channel[i].xfermode          = 0;
-    channel[i].destaddr          = 0;
-    channel[i].srcaddr           = 0;
-    channel[i].xfersize          = 0x0000;
+    channel[i].dmap              = 0xff;
+    channel[i].direction         = 1;
+    channel[i].hdma_indirect     = 1;
+    channel[i].incmode           = -1;
+    channel[i].fixedxfer         = 1;
+    channel[i].xfermode          = 7;
+    channel[i].destaddr          = 0xff;
+    channel[i].srcaddr           = 0xffff;
+    channel[i].srcbank           = 0xff;
+    channel[i].xfersize          = 0xffff;
   //xfersize and hdma_iaddr are of union { uint16 };
-  //channel[i].hdma_iaddr        = 0x0000;
-    channel[i].hdma_ibank        = 0;
-    channel[i].hdma_addr         = 0x0000;
-    channel[i].hdma_line_counter = 0x00;
-    channel[i].hdma_unknown      = 0x00;
+  //channel[i].hdma_iaddr        = 0xffff;
+    channel[i].hdma_ibank        = 0xff;
+    channel[i].hdma_addr         = 0xffff;
+    channel[i].hdma_line_counter = 0xff;
+    channel[i].hdma_unknown      = 0xff;
 
     channel[i].hdma_active       = false;
     channel[i].hdma_do_transfer  = false;
diff --git a/src/cpu/bcpu/memory/memory.cpp b/src/cpu/bcpu/memory/memory.cpp
index 8e702df3..c4ea39ee 100644
--- a/src/cpu/bcpu/memory/memory.cpp
+++ b/src/cpu/bcpu/memory/memory.cpp
@@ -34,6 +34,7 @@ void bCPU::mem_write(uint32 addr, uint8 value) {
   status.cycle_count = r_mem->speed(addr);
   pre_exec_cycle();
   add_cycles(status.cycle_count);
+  regs.mdr = value;
   r_mem->write(addr, value);
   cycle_edge();
 }
diff --git a/src/lib/libwin32.cpp b/src/lib/libwin32.cpp
index 84b9db0b..309878a4 100644
--- a/src/lib/libwin32.cpp
+++ b/src/lib/libwin32.cpp
@@ -1,6 +1,7 @@
 #include "libbase.h"
 #include "libwin32.h"
 
+#include "libwin32_misc.cpp"
 #include "libwin32_file.cpp"
 #include "libwin32_window.cpp"
 #include "libwin32_control.cpp"
diff --git a/src/lib/libwin32.h b/src/lib/libwin32.h
index 531f4ddf..5056c77c 100644
--- a/src/lib/libwin32.h
+++ b/src/lib/libwin32.h
@@ -7,8 +7,8 @@
 
 #include "libstring.h"
 
-#define WINVER       0x0501
-#define _WIN32_WINNT 0x0501
+#define WINVER       0x0400
+#define _WIN32_WINNT 0x0400
 #include <windows.h>
 #include <commctrl.h>
 #include <direct.h>
diff --git a/src/lib/libwin32_misc.cpp b/src/lib/libwin32_misc.cpp
new file mode 100644
index 00000000..02f0e39c
--- /dev/null
+++ b/src/lib/libwin32_misc.cpp
@@ -0,0 +1,33 @@
+#ifndef WS_EX_LAYERED
+#define WS_EX_LAYERED 0x00080000
+#endif
+
+typedef BOOL (WINAPI *SLWAProc)(HWND hwnd, COLORREF crKey, BYTE bAlpha, DWORD dwFlags);
+
+#ifndef LWA_COLORKEY
+#define LWA_COLORKEY 0x00000001
+#endif
+
+#ifndef LWA_ALPHA
+#define LWA_ALPHA 0x0000002
+#endif
+
+BOOL SetWindowAlphaLevel(HWND hwnd, uint level) {
+SLWAProc pSLWA;
+HMODULE handle = GetModuleHandle("USER32.DLL");
+BOOL result;
+  if(!handle)return FALSE;
+  pSLWA = (SLWAProc)GetProcAddress(handle, (char*)"SetLayeredWindowAttributes");
+  if(pSLWA == 0)return FALSE;
+
+  level &= 255;
+  if(level != 255) {
+    SetWindowLong(hwnd, GWL_EXSTYLE, GetWindowLong(hwnd, GWL_EXSTYLE) | WS_EX_LAYERED);
+    result = pSLWA(hwnd, 0, level, LWA_ALPHA);
+  } else {
+    SetWindowLong(hwnd, GWL_EXSTYLE, GetWindowLong(hwnd, GWL_EXSTYLE) & ~WS_EX_LAYERED);
+    result = pSLWA(hwnd, 0, 0, 0);
+  }
+  InvalidateRect(hwnd, 0, TRUE);
+  return result;
+}
diff --git a/src/lib/libwin32_window.cpp b/src/lib/libwin32_window.cpp
index e2004459..bf4cf477 100644
--- a/src/lib/libwin32_window.cpp
+++ b/src/lib/libwin32_window.cpp
@@ -291,15 +291,11 @@ string part;
 void Window::SetAlphaLevel(uint level) {
   level &= 255;
   if(level == 255) {
-  //no reason to use layered attribute for completely opaque window
     state.es &= ~WS_EX_LAYERED;
-    SetWindowLong(hwnd, GWL_EXSTYLE, state.es);
-    SetLayeredWindowAttributes(hwnd, 0, 0, 0);
   } else {
     state.es |=  WS_EX_LAYERED;
-    SetWindowLong(hwnd, GWL_EXSTYLE, state.es);
-    SetLayeredWindowAttributes(hwnd, 0, level, LWA_ALPHA);
   }
+  SetWindowAlphaLevel(hwnd, level);
 }
 
 void Window::SetBackgroundColor(uint r, uint g, uint b) {
diff --git a/src/ppu/bppu/bppu.cpp b/src/ppu/bppu/bppu.cpp
index eda98ffb..8f2f2829 100644
--- a/src/ppu/bppu/bppu.cpp
+++ b/src/ppu/bppu/bppu.cpp
@@ -123,10 +123,12 @@ void bPPU::reset() {
 //$2102-$2103
   regs.oam_baseaddr    = 0x0000;
   regs.oam_addr        = 0x0000;
-  regs.oam_latchdata   = 0x00;
   regs.oam_priority    = false;
   regs.oam_firstsprite = 0x00;
 
+//$2104
+  regs.oam_latchdata   = 0x00;
+
 //$2105
   regs.bg_tilesize[BG1] = 0;
   regs.bg_tilesize[BG2] = 0;
@@ -193,6 +195,9 @@ void bPPU::reset() {
 //$2121
   regs.cgram_addr = 0x0000;
 
+//$2122
+  regs.cgram_latchdata = 0x00;
+
 //$2123-$2125
   regs.window1_enabled[BG1] = false;
   regs.window1_enabled[BG2] = false;
diff --git a/src/ppu/bppu/bppu.h b/src/ppu/bppu/bppu.h
index 2b28c0e8..26691976 100644
--- a/src/ppu/bppu/bppu.h
+++ b/src/ppu/bppu/bppu.h
@@ -33,10 +33,12 @@ struct {
 //$2102-$2103
   uint16 oam_baseaddr;
   uint16 oam_addr;
-  uint8  oam_latchdata;
   bool   oam_priority;
   uint8  oam_firstsprite;
 
+//$2104
+  uint8  oam_latchdata;
+
 //$2105
   bool   bg_tilesize[4];
   bool   bg3_priority;
@@ -81,6 +83,9 @@ struct {
 //$2121
   uint16 cgram_addr;
 
+//$2122
+  uint8  cgram_latchdata;
+
 //$2123-$2125
   bool   window1_enabled[6];
   bool   window1_invert [6];
diff --git a/src/ppu/bppu/bppu_mmio.cpp b/src/ppu/bppu/bppu_mmio.cpp
index cdb1e411..d90eddf9 100644
--- a/src/ppu/bppu/bppu_mmio.cpp
+++ b/src/ppu/bppu/bppu_mmio.cpp
@@ -94,15 +94,16 @@ void bPPU::mmio_w2103(uint8 value) {
 //OAMDATA
 void bPPU::mmio_w2104(uint8 value) {
   if(regs.oam_addr >= 0x0200) {
-    if(!(regs.oam_addr & 1)) {
-      regs.oam_latchdata = value;
-    }
+  //does this happen?
+  //if(!(regs.oam_addr & 1)) {
+  //  regs.oam_latchdata = value;
+  //}
     oam_write(regs.oam_addr, value);
   } else if(!(regs.oam_addr & 1)) {
     regs.oam_latchdata = value;
   } else {
-    oam_write((regs.oam_addr & 0x03fe),     regs.oam_latchdata);
-    oam_write((regs.oam_addr & 0x03fe) + 1, value);
+    oam_write((regs.oam_addr & 0x01fe),     regs.oam_latchdata);
+    oam_write((regs.oam_addr & 0x01fe) + 1, value);
   }
   regs.oam_addr++;
   regs.oam_addr &= 0x03ff;
@@ -336,11 +337,17 @@ void bPPU::mmio_w2121(uint8 value) {
 //note: CGRAM palette data format is 15-bits
 //(0,bbbbb,ggggg,rrrrr). Highest bit is ignored,
 //as evidenced by $213b CGRAM data reads.
+//
+//anomie indicates writes to CGDATA work the same
+//as writes to OAMDATA's low table. need to verify
+//this on hardware.
 void bPPU::mmio_w2122(uint8 value) {
-  if(regs.cgram_addr & 1) {
-    value &= 0x7f;
+  if(!(regs.cgram_addr & 1)) {
+    regs.cgram_latchdata = value;
+  } else {
+    cgram_write((regs.cgram_addr & 0x01fe),     regs.cgram_latchdata);
+    cgram_write((regs.cgram_addr & 0x01fe) + 1, value & 0x7f);
   }
-  cgram_write(regs.cgram_addr, value);
   regs.cgram_addr++;
   regs.cgram_addr &= 0x01ff;
 }
@@ -526,9 +533,12 @@ uint8 bPPU::mmio_r2137() {
 //OAMDATAREAD
 uint8 bPPU::mmio_r2138() {
   regs.ppu1_mdr = oam_read(regs.oam_addr);
-  if(!(regs.oam_addr & 1)) {
-    regs.oam_latchdata = regs.ppu1_mdr;
-  }
+//DMV27: OAM writes do not affect latch data
+//byuu: Even if they do, this should only affect the low table
+//byuu: Disable for now, see what happens... test on hardware
+//if(!(regs.oam_addr & 1)) {
+//  regs.oam_latchdata = regs.ppu1_mdr;
+//}
   regs.oam_addr++;
   regs.oam_addr &= 0x03ff;
   return regs.ppu1_mdr;
diff --git a/src/sdl/Makefile b/src/sdl/Makefile
index c49a9f84..0afba2ea 100644
--- a/src/sdl/Makefile
+++ b/src/sdl/Makefile
@@ -4,14 +4,14 @@ CFLAGS = -O3 -fomit-frame-pointer -ffast-math
 CXXFLAGS = $(CFLAGS) -fno-rtti
 OBJS = sdlmain.o \
        libstring.o libconfig.o libbpf.o \
-       reader.o cart.o \
+       reader.o cart.o cheat.o \
        memory.o bmemory.o \
        cpu.o bcpu.o \
        apu.o bapu.o \
        bdsp.o \
        ppu.o bppu.o \
        snes.o \
-       srtc.o sdd1.o c4.o \
+       srtc.o sdd1.o c4.o dsp2.o obc1.o \
        adler32.o compress.o crc32.o deflate.o gzio.o inffast.o \
        inflate.o inftrees.o ioapi.o trees.o unzip.o zip.o zutil.o \
        jma.o jcrc32.o lzmadec.o 7zlzma.o iiostrm.o inbyte.o lzma.o winout.o
@@ -89,6 +89,9 @@ reader.o: ../reader/*.cpp ../reader/*.h
 cart.o: ../cart/*.cpp ../cart/*.h
 	$(CXX) $(CXXFLAGS) -c ../cart/cart.cpp
 
+cheat.o: ../cheat/*.cpp ../cheat/*.h
+	$(CXX) $(CXXFLAGS) -c ../cheat/cheat.cpp
+
 ############
 ### snes ###
 ############
@@ -107,6 +110,12 @@ sdd1.o: ../chip/sdd1/*.cpp ../chip/sdd1/*.h
 c4.o: ../chip/c4/*.cpp ../chip/c4/*.h
 	$(CXX) $(CXXFLAGS) -c ../chip/c4/c4.cpp
 
+dsp2.o: ../chip/dsp2/*.cpp ../chip/dsp2/*.h
+	$(CXX) $(CXXFLAGS) -c ../chip/dsp2/dsp2.cpp
+
+obc1.o: ../chip/obc1/*.cpp ../chip/obc1/*.h
+	$(CXX) $(CXXFLAGS) -c ../chip/obc1/obc1.cpp
+
 ############
 ### zlib ###
 ############
diff --git a/src/sdl/bsnes_sdl.cfg b/src/sdl/bsnes_sdl.cfg
deleted file mode 100644
index cc1ac3db..00000000
--- a/src/sdl/bsnes_sdl.cfg
+++ /dev/null
@@ -1,98 +0,0 @@
-# Default path to look for ROM files in ("" = use default directory)
-# (default = "")
-fs.rom_path = ""
-
-# Default path for all save RAM files ("" = use current directory)
-# (default = "")
-fs.sram_path = ""
-
-# Extension to be used for all save RAM files
-# (default = "srm")
-fs.sram_ext = "srm"
-
-# Applies contrast adjust filter to video output when enabled
-# Works by lowering the brightness of darker colors,
-# while leaving brighter colors alone; thus reducing saturation
-# (default = true)
-snes.video_color_curve = true
-
-# Selects color adjustment filter for video output
-#   0 = Normal (no filter, rgb555)
-#   1 = Grayscale mode (l5)
-#   2 = VGA mode (rgb332)
-#   3 = Genesis mode (rgb333)
-# (default = 0)
-snes.video_color_adjust_mode = 0
-
-# Mutes SNES audio output when enabled
-# (default = false)
-snes.mute = true
-
-# Enable fullscreen mode at startup
-# (default = false)
-video.fullscreen = false
-
-# Window / Fullscreen width
-# (default = 320)
-video.display_width = 320
-
-# Window / Fullscreen height
-# (default = 240)
-video.display_height = 240
-
-# SNES video output width
-# (default = 256)
-video.output_width = 256
-
-# SNES video output height
-# (default = 223)
-video.output_height = 223
-
-# Joypad1 up
-# (default = 0x111)
-input.joypad1.up = 0x111
-
-# Joypad1 down
-# (default = 0x112)
-input.joypad1.down = 0x112
-
-# Joypad1 left
-# (default = 0x114)
-input.joypad1.left = 0x114
-
-# Joypad1 right
-# (default = 0x113)
-input.joypad1.right = 0x113
-
-# Joypad1 A
-# (default = 0x78)
-input.joypad1.a = 0x78
-
-# Joypad1 B
-# (default = 0x7a)
-input.joypad1.b = 0x7a
-
-# Joypad1 X
-# (default = 0x73)
-input.joypad1.x = 0x73
-
-# Joypad1 Y
-# (default = 0x61)
-input.joypad1.y = 0x61
-
-# Joypad1 L
-# (default = 0x64)
-input.joypad1.l = 0x64
-
-# Joypad1 R
-# (default = 0x63)
-input.joypad1.r = 0x63
-
-# Joypad1 select
-# (default = 0x12f)
-input.joypad1.select = 0x12f
-
-# Joypad1 start
-# (default = 0xd)
-input.joypad1.start = 0xd
-
diff --git a/src/win/event.cpp b/src/win/event.cpp
index 23effcfa..42679dda 100644
--- a/src/win/event.cpp
+++ b/src/win/event.cpp
@@ -97,7 +97,7 @@ string dir;
 
   if(!GetOpenFileName(&ofn))return;
 
-  cartridge.unload();
+  if(cartridge.loaded() == true)cartridge.unload();
   wDebug.Clear();
 
   cartridge.load(t);
@@ -107,6 +107,8 @@ string dir;
 }
 
 void unload_rom() {
+  if(cartridge.loaded() == false)return;
+
   cartridge.unload();
   uiVideo->clear_video();
   uiAudio->clear_audio();
diff --git a/src/win/main.cpp b/src/win/main.cpp
index bf6948c8..49238639 100644
--- a/src/win/main.cpp
+++ b/src/win/main.cpp
@@ -103,7 +103,7 @@ MSG msg;
   }
 
 _end:
-  cartridge.unload();
+  if(cartridge.loaded() == true)cartridge.unload();
 
   term_ui();
   term_snes();
diff --git a/src/win/ui.h b/src/win/ui.h
index e5024353..16762c44 100644
--- a/src/win/ui.h
+++ b/src/win/ui.h
@@ -62,6 +62,7 @@ MENU_SETTINGS,
 MENU_MISC,
   MENU_MISC_SCREENSHOT,
   MENU_MISC_LOGAUDIO,
+  MENU_MISC_CHEATEDITOR,
 //---
   MENU_MISC_ABOUT,
 };
diff --git a/src/win/ui_main.cpp b/src/win/ui_main.cpp
index 6f772651..19108a7d 100644
--- a/src/win/ui_main.cpp
+++ b/src/win/ui_main.cpp
@@ -132,13 +132,17 @@ bool MainWindow::Event(EventInfo &info) {
     } break;
 
     case MENU_FILE_RESET: {
-      bsnes->reset();
-      dprintf("* Reset");
+      if(cartridge.loaded() == true) {
+        bsnes->reset();
+        dprintf("* Reset");
+      }
     } break;
 
     case MENU_FILE_POWER: {
-      bsnes->power();
-      dprintf("* Power");
+      if(cartridge.loaded() == true) {
+        bsnes->power();
+        dprintf("* Power");
+      }
     } break;
 
     case MENU_FILE_EXIT: {
@@ -217,6 +221,11 @@ bool MainWindow::Event(EventInfo &info) {
       }
     } break;
 
+    case MENU_MISC_CHEATEDITOR: {
+      settings.set_active_panel(&wCheatEditor);
+      wSettings.Show();
+    } break;
+
     case MENU_MISC_ABOUT: {
       wAbout.Show();
     } break;
@@ -303,8 +312,9 @@ char t[128];
   EndMenuGroup();
 
   AddMenuGroup("&Misc");
-    AddMenuItem(MENU_MISC_SCREENSHOT, "&Capture Screenshot");
-    AddMenuItem(MENU_MISC_LOGAUDIO,   "&Log Audio Data");
+    AddMenuItem(MENU_MISC_SCREENSHOT,  "Capture &Screenshot");
+    AddMenuItem(MENU_MISC_LOGAUDIO,    "&Log Audio Data");
+    AddMenuItem(MENU_MISC_CHEATEDITOR, "&Cheat Code Editor");
     AddMenuSeparator();
     AddMenuItem(MENU_MISC_ABOUT,      "&About");
   EndMenuGroup();