diff --git a/bsnes/base/base.hpp b/bsnes/base/base.hpp
index 06f92f31..2c04c072 100755
--- a/bsnes/base/base.hpp
+++ b/bsnes/base/base.hpp
@@ -1,7 +1,7 @@
 #ifndef BASE_HPP
 #define BASE_HPP
 
-static const char Version[] = "087.23";
+static const char Version[] = "087.25";
 
 #include <nall/platform.hpp>
 #include <nall/algorithm.hpp>
diff --git a/bsnes/data/GBA.system/manifest.xml b/bsnes/data/GBA.system/manifest.xml
new file mode 100755
index 00000000..f6b52ae0
--- /dev/null
+++ b/bsnes/data/GBA.system/manifest.xml
@@ -0,0 +1,4 @@
+<?xml version='1.0' encoding='UTF-8'?>
+<system type="GBA">
+  <bios firmware="bios.rom" sha256="fd2547724b505f487e6dcb29ec2ecff3af35a841a77ab2e85fd87350abd36570"/>
+</system>
diff --git a/bsnes/gba/cpu/cpu.cpp b/bsnes/gba/cpu/cpu.cpp
index 47294b90..3a370207 100755
--- a/bsnes/gba/cpu/cpu.cpp
+++ b/bsnes/gba/cpu/cpu.cpp
@@ -45,6 +45,11 @@ void CPU::step(unsigned clocks) {
   if(apu.clock < 0) co_switch(apu.thread);
 }
 
+void CPU::bus_idle(uint32 addr) {
+  step(1);
+  return bus.idle(addr);
+}
+
 uint32 CPU::bus_read(uint32 addr, uint32 size) {
   step(bus.speed(addr, size));
   return bus.read(addr, size);
diff --git a/bsnes/gba/cpu/cpu.hpp b/bsnes/gba/cpu/cpu.hpp
index 7e5ea11a..d2c2cc6e 100755
--- a/bsnes/gba/cpu/cpu.hpp
+++ b/bsnes/gba/cpu/cpu.hpp
@@ -8,6 +8,7 @@ struct CPU : Processor::ARM, Thread, MMIO {
   void enter();
   void step(unsigned clocks);
 
+  void bus_idle(uint32 addr);
   uint32 bus_read(uint32 addr, uint32 size);
   void bus_write(uint32 addr, uint32 size, uint32 word);
 
diff --git a/bsnes/gba/cpu/registers.cpp b/bsnes/gba/cpu/registers.cpp
index 600588a5..43ce04c2 100755
--- a/bsnes/gba/cpu/registers.cpp
+++ b/bsnes/gba/cpu/registers.cpp
@@ -112,13 +112,13 @@ uint16 CPU::Registers::Interrupt::operator=(uint16 source) {
 
 CPU::Registers::WaitControl::operator uint16() const {
   return (
-    (sram     <<  0)
-  | (wait0n   <<  2)
-  | (wait0s   <<  4)
-  | (wait1n   <<  5)
-  | (wait1s   <<  7)
-  | (wait2n   <<  8)
-  | (wait2s   << 10)
+    (nwait[3] <<  0)
+  | (nwait[0] <<  2)
+  | (swait[0] <<  4)
+  | (nwait[1] <<  5)
+  | (swait[1] <<  7)
+  | (nwait[2] <<  8)
+  | (swait[2] << 10)
   | (phi      << 11)
   | (prefetch << 14)
   | (gametype << 15)
@@ -126,16 +126,17 @@ CPU::Registers::WaitControl::operator uint16() const {
 }
 
 uint16 CPU::Registers::WaitControl::operator=(uint16 source) {
-  sram     = (source >>  0) & 3;
-  wait0n   = (source >>  2) & 3;
-  wait0s   = (source >>  4) & 1;
-  wait1n   = (source >>  5) & 3;
-  wait1s   = (source >>  7) & 1;
-  wait2n   = (source >>  8) & 3;
-  wait2s   = (source >> 10) & 1;
+  nwait[3] = (source >>  0) & 3;
+  nwait[0] = (source >>  2) & 3;
+  swait[0] = (source >>  4) & 1;
+  nwait[1] = (source >>  5) & 3;
+  swait[1] = (source >>  7) & 1;
+  nwait[2] = (source >>  8) & 3;
+  swait[2] = (source >> 10) & 1;
   phi      = (source >> 11) & 3;
   prefetch = (source >> 14) & 1;
   gametype = (source >> 15) & 1;
+  swait[3] = nwait[3];
   return operator uint16();
 }
 
diff --git a/bsnes/gba/cpu/registers.hpp b/bsnes/gba/cpu/registers.hpp
index bf439a82..98b5cda8 100755
--- a/bsnes/gba/cpu/registers.hpp
+++ b/bsnes/gba/cpu/registers.hpp
@@ -91,13 +91,8 @@ struct Registers {
   } irq;
 
   struct WaitControl {
-    uint2 sram;
-    uint2 wait0n;
-    uint1 wait0s;
-    uint2 wait1n;
-    uint1 wait1s;
-    uint2 wait2n;
-    uint1 wait2s;
+    uint2 nwait[4];
+    uint2 swait[4];
     uint2 phi;
     uint1 prefetch;
     uint1 gametype;
diff --git a/bsnes/gba/memory/memory.cpp b/bsnes/gba/memory/memory.cpp
index 9e4a3c8a..b4c02f4e 100755
--- a/bsnes/gba/memory/memory.cpp
+++ b/bsnes/gba/memory/memory.cpp
@@ -74,62 +74,77 @@ uint32 Bus::mirror(uint32 addr, uint32 size) {
 }
 
 uint32 Bus::speed(uint32 addr, uint32 size) {
-  return 2;
+  if(addr & 0x08000000) {
+    static unsigned timing[] = { 5, 4, 3, 9 };
+    unsigned n = cpu.regs.wait.control.nwait[addr >> 25 & 3];
+    unsigned s = cpu.regs.wait.control.swait[addr >> 25 & 3];
 
-                           //B  B  E  I  M  P  V  O  R  R  R  R  R  R  S  S
-                           //I  I  R  R  M  R  R  A  O  O  O  O  O  O  R  R
-                           //O  O  A  A  I  A  A  M  M  M  M  M  M  M  A  A
-                           //S  S  M  M  O  M  M                       M  M
-  static unsigned byte[] = { 1, 1, 3, 1, 1, 1, 1, 1, 5, 5, 5, 5, 5, 5, 5, 5 };
-  static unsigned half[] = { 1, 1, 3, 1, 1, 1, 1, 1, 5, 5, 5, 5, 5, 5, 5, 5 };
-  static unsigned word[] = { 1, 1, 6, 1, 1, 2, 2, 1, 8, 8, 8, 8, 8, 8, 8, 8 };
+    bool sequential = cpu.sequential();
+    if((addr & 0xffff << 1) == 0) sequential = false;
+    if(idleflag) sequential = false;
 
-  addr = (addr >> 24) & 15;
-  switch(size) {
-  case Byte: return byte[addr];
-  case Half: return half[addr];
-  case Word: return word[addr];
+    if(sequential) return s << (size == Word);  //16-bit bus
+    if(size == Word) n += s;
+    return n;
+  }
+
+  switch(addr >> 24 & 7) {
+  case 0: return 1;
+  case 1: return 1;
+  case 2: return 3 << (size == Word);
+  case 3: return 1;
+  case 4: return 1;
+  case 5: return 1 << (size == Word);
+  case 6: return 1 << (size == Word);
+  case 7: return 1;
   }
 }
 
+void Bus::idle(uint32 addr) {
+  if(addr & 0x08000000) idleflag = true;
+}
+
 uint32 Bus::read(uint32 addr, uint32 size) {
+  idleflag = false;
   if(addr & 0x08000000) return cartridge.read(addr, size);
 
-  switch(addr & 0x07000000) {
-  case 0x00000000: return bios.read(addr, size);
-  case 0x01000000: return bios.read(addr, size);
-  case 0x02000000: return cpu.ewram.read(addr & 0x3ffff, size);
-  case 0x03000000: return cpu.iwram.read(addr & 0x7fff, size);
-  case 0x04000000:
+  switch(addr >> 24 & 7) {
+  case 0: return bios.read(addr, size);
+  case 1: return bios.read(addr, size);
+  case 2: return cpu.ewram.read(addr & 0x3ffff, size);
+  case 3: return cpu.iwram.read(addr & 0x7fff, size);
+  case 4:
     if((addr & 0xfffffc00) == 0x04000000) return mmio[addr & 0x3ff]->read(addr, size);
     if((addr & 0xff00ffff) == 0x04000800) return ((MMIO&)cpu).read(0x04000800 | (addr & 3), size);
     return 0u;
-  case 0x05000000: return ppu.pram_read(addr, size);
-  case 0x06000000: return ppu.vram_read(addr, size);
-  case 0x07000000: return ppu.oam_read(addr, size);
+  case 5: return ppu.pram_read(addr, size);
+  case 6: return ppu.vram_read(addr, size);
+  case 7: return ppu.oam_read(addr, size);
   }
 }
 
 void Bus::write(uint32 addr, uint32 size, uint32 word) {
+  idleflag = false;
   if(addr & 0x08000000) return cartridge.write(addr, size, word);
 
-  switch(addr & 0x07000000) {
-  case 0x00000000: return;
-  case 0x01000000: return;
-  case 0x02000000: return cpu.ewram.write(addr & 0x3ffff, size, word);
-  case 0x03000000: return cpu.iwram.write(addr & 0x7fff, size, word);
-  case 0x04000000:
+  switch(addr >> 24 & 7) {
+  case 0: return;
+  case 1: return;
+  case 2: return cpu.ewram.write(addr & 0x3ffff, size, word);
+  case 3: return cpu.iwram.write(addr & 0x7fff, size, word);
+  case 4:
     if((addr & 0xfffffc00) == 0x04000000) return mmio[addr & 0x3ff]->write(addr, size, word);
     if((addr & 0xff00ffff) == 0x04000800) return ((MMIO&)cpu).write(0x04000800 | (addr & 3), size, word);
     return;
-  case 0x05000000: return ppu.pram_write(addr, size, word);
-  case 0x06000000: return ppu.vram_write(addr, size, word);
-  case 0x07000000: return ppu.oam_write(addr, size, word);
+  case 5: return ppu.pram_write(addr, size, word);
+  case 6: return ppu.vram_write(addr, size, word);
+  case 7: return ppu.oam_write(addr, size, word);
   }
 }
 
 void Bus::power() {
   for(unsigned n = 0; n < 0x400; n++) mmio[n] = &unmappedMemory;
+  idleflag = false;
 }
 
 }
diff --git a/bsnes/gba/memory/memory.hpp b/bsnes/gba/memory/memory.hpp
index 5c9adf70..743b0caa 100755
--- a/bsnes/gba/memory/memory.hpp
+++ b/bsnes/gba/memory/memory.hpp
@@ -23,9 +23,11 @@ struct MMIO : Memory {
 
 struct Bus : Memory {
   Memory *mmio[0x400];
+  bool idleflag;
   static uint32 mirror(uint32 addr, uint32 size);
 
   uint32 speed(uint32 addr, uint32 size);
+  void idle(uint32 addr);
   uint32 read(uint32 addr, uint32 size);
   void write(uint32 addr, uint32 size, uint32 word);
   void power();
diff --git a/bsnes/gba/ppu/object.cpp b/bsnes/gba/ppu/object.cpp
index 82e5b376..ca2d2ae6 100755
--- a/bsnes/gba/ppu/object.cpp
+++ b/bsnes/gba/ppu/object.cpp
@@ -56,7 +56,7 @@ void PPU::render_object(Object &obj) {
       x = (x / (1 + regs.mosaic.objhsize)) * (1 + regs.mosaic.objhsize);
     }
 
-    unsigned ox = obj.x + px;
+    uint9 ox = obj.x + px;
     if(ox < 240 && x < obj.width && y < obj.height) {
       unsigned offset = (y / 8) * rowsize + (x / 8);
       offset = offset * 64 + (y & 7) * 8 + (x & 7);
diff --git a/bsnes/processor/arm/algorithms.cpp b/bsnes/processor/arm/algorithms.cpp
index 42b5c1ae..8eb5d6bb 100755
--- a/bsnes/processor/arm/algorithms.cpp
+++ b/bsnes/processor/arm/algorithms.cpp
@@ -55,63 +55,40 @@ uint32 ARM::mul(uint32 product, uint32 multiplicand, uint32 multiplier) {
   return product;
 }
 
-uint32 ARM::lsl(uint32 source, uint32 shift) {
-  while(shift--) {
-    carryout() = source >> 31;
-    source <<= 1;
-  }
-
-  if(cpsr().t) {
-    cpsr().n = source >> 31;
-    cpsr().z = source == 0;
-    cpsr().c = carryout();
-  }
+uint32 ARM::lsl(uint32 source, uint8 shift) {
+  carryout() = cpsr().c;
+  if(shift == 0) return source;
 
+  carryout() = shift > 32 ? 0 : source & (1 << 32 - shift);
+  source     = shift > 31 ? 0 : source << shift;
   return source;
 }
 
-uint32 ARM::lsr(uint32 source, uint32 shift) {
-  while(shift--) {
-    carryout() = source & 1;
-    source >>= 1;
-  }
-
-  if(cpsr().t) {
-    cpsr().n = source >> 31;
-    cpsr().z = source == 0;
-    cpsr().c = carryout();
-  }
+uint32 ARM::lsr(uint32 source, uint8 shift) {
+  carryout() = cpsr().c;
+  if(shift == 0) return source;
 
+  carryout() = shift > 32 ? 0 : source & (1 << shift - 1);
+  source     = shift > 31 ? 0 : source >> shift;
   return source;
 }
 
-uint32 ARM::asr(uint32 source, uint32 shift) {
-  while(shift--) {
-    carryout() = source & 1;
-    source = (int32)source >> 1;
-  }
-
-  if(cpsr().t) {
-    cpsr().n = source >> 31;
-    cpsr().z = source == 0;
-    cpsr().c = carryout();
-  }
+uint32 ARM::asr(uint32 source, uint8 shift) {
+  carryout() = cpsr().c;
+  if(shift == 0) return source;
 
+  carryout() = shift > 32 ? source & (1 << 31) : source & (1 << shift - 1);
+  source     = shift > 31 ? (int32)source >> 31 : (int32)source >> shift;
   return source;
 }
 
-uint32 ARM::ror(uint32 source, uint32 shift) {
-  while(shift--) {
-    carryout() = source & 1;
-    source = (source << 31) | (source >> 1);
-  }
-
-  if(cpsr().t) {
-    cpsr().n = source >> 31;
-    cpsr().z = source == 0;
-    cpsr().c = carryout();
-  }
+uint32 ARM::ror(uint32 source, uint8 shift) {
+  carryout() = cpsr().c;
+  if(shift == 0) return source;
 
+  if(shift &= 31)
+  source     = source << 32 - shift | source >> shift;
+  carryout() = source & (1 << 31);
   return source;
 }
 
diff --git a/bsnes/processor/arm/arm.cpp b/bsnes/processor/arm/arm.cpp
index 5f70e0b5..a3734dc3 100755
--- a/bsnes/processor/arm/arm.cpp
+++ b/bsnes/processor/arm/arm.cpp
@@ -26,16 +26,43 @@ void ARM::exec() {
   cpsr().t ? thumb_step() : arm_step();
 }
 
+void ARM::idle() {
+  bus_idle(r(15));
+}
+
 uint32 ARM::read(uint32 addr, uint32 size) {
   uint32 word = bus_read(addr, size);
-//uint32 rotate = (addr & 3) << 3;
-//word = (word >> rotate) | (word << (32 - rotate));
-//word = word & (~0u >> (32 - size));
+  sequential() = true;
+  return word;
+}
+
+uint32 ARM::load(uint32 addr, uint32 size) {
+  sequential() = false;
+  uint32 word = read(addr, size);
+
+  if(size == Half) { word &= 0xffff; word |= word << 16; }
+  if(size == Byte) { word &= 0xff; word |= word << 8; word |= word << 16; }
+
+  word = ror(word, 8 * (addr & 3));
+  idle();
+
+  if(size == Half) word &= 0xffff;
+  if(size == Byte) word &= 0xff;
   return word;
 }
 
 void ARM::write(uint32 addr, uint32 size, uint32 word) {
-  return bus_write(addr, size, word);
+  bus_write(addr, size, word);
+  sequential() = true;
+}
+
+void ARM::store(uint32 addr, uint32 size, uint32 word) {
+  if(size == Half) { word &= 0xffff; word |= word << 16; }
+  if(size == Byte) { word &= 0xff; word |= word << 8; word |= word << 16; }
+
+  sequential() = false;
+  write(addr, size, word);
+  sequential() = false;
 }
 
 void ARM::vector(uint32 addr, Processor::Mode mode) {
@@ -43,7 +70,7 @@ void ARM::vector(uint32 addr, Processor::Mode mode) {
   processor.setMode(mode);
   spsr() = psr;
   cpsr().i = 1;
-  cpsr().f = mode == Processor::Mode::FIQ;
+  cpsr().f |= mode == Processor::Mode::FIQ;
   cpsr().t = 0;
   r(14) = pipeline.decode.address;
   r(15) = addr;
diff --git a/bsnes/processor/arm/arm.hpp b/bsnes/processor/arm/arm.hpp
index 0b2e0e42..38b58d61 100755
--- a/bsnes/processor/arm/arm.hpp
+++ b/bsnes/processor/arm/arm.hpp
@@ -3,7 +3,8 @@
 
 namespace Processor {
 
-//ARMv3, ARMv4TM
+//ARMv3
+//ARMv4TDMI
 
 struct ARM {
   enum : unsigned { Byte = 8, Half = 16, Word = 32 };
@@ -12,13 +13,17 @@ struct ARM {
   #include "instructions-thumb.hpp"
   #include "disassembler.hpp"
   virtual void step(unsigned clocks) = 0;
+  virtual void bus_idle(uint32 addr) = 0;
   virtual uint32 bus_read(uint32 addr, uint32 size) = 0;
   virtual void bus_write(uint32 addr, uint32 size, uint32 word) = 0;
 
   void power();
   void exec();
+  void idle();
   uint32 read(uint32 addr, uint32 size);
+  uint32 load(uint32 addr, uint32 size);
   void write(uint32 addr, uint32 size, uint32 word);
+  void store(uint32 addr, uint32 size, uint32 word);
   void vector(uint32 addr, Processor::Mode mode);
 
   bool condition(uint4 condition);
@@ -26,10 +31,10 @@ struct ARM {
   uint32 add(uint32 source, uint32 modify, bool carry);
   uint32 sub(uint32 source, uint32 modify, bool carry);
   uint32 mul(uint32 product, uint32 multiplicand, uint32 multiplier);
-  uint32 lsl(uint32 source, uint32 shift);
-  uint32 lsr(uint32 source, uint32 shift);
-  uint32 asr(uint32 source, uint32 shift);
-  uint32 ror(uint32 source, uint32 shift);
+  uint32 lsl(uint32 source, uint8 shift);
+  uint32 lsr(uint32 source, uint8 shift);
+  uint32 asr(uint32 source, uint8 shift);
+  uint32 ror(uint32 source, uint8 shift);
   uint32 rrx(uint32 source);
 
   void serialize(serializer&);
diff --git a/bsnes/processor/arm/instructions-arm.cpp b/bsnes/processor/arm/instructions-arm.cpp
index fca10cc1..b4369aef 100755
--- a/bsnes/processor/arm/instructions-arm.cpp
+++ b/bsnes/processor/arm/instructions-arm.cpp
@@ -5,6 +5,7 @@ void ARM::arm_step() {
     pipeline.reload = false;
     r(15).data &= ~3;
 
+    sequential() = false;
     pipeline.fetch.address = r(15) & ~3;
     pipeline.fetch.instruction = read(pipeline.fetch.address, Word);
 
@@ -195,8 +196,8 @@ void ARM::arm_op_memory_swap() {
   uint4 d = instruction() >> 12;
   uint4 m = instruction();
 
-  uint32 word = read(r(n), byte ? Byte : Word);
-  write(r(n), byte ? Byte : Word, r(m));
+  uint32 word = load(r(n), byte ? Byte : Word);
+  store(r(n), byte ? Byte : Word, r(m));
   r(d) = word;
 }
 
@@ -215,7 +216,7 @@ void ARM::arm_op_move_half_register() {
   uint1 pre = instruction() >> 24;
   uint1 up = instruction() >> 23;
   uint1 writeback = instruction() >> 21;
-  uint1 load = instruction() >> 20;
+  uint1 l = instruction() >> 20;
   uint4 n = instruction() >> 16;
   uint4 d = instruction() >> 12;
   uint4 m = instruction();
@@ -224,8 +225,8 @@ void ARM::arm_op_move_half_register() {
   uint32 rm = r(m);
 
   if(pre == 1) rn = up ? rn + rm : rn - rm;
-  if(load == 1) r(d) = read(rn, Half);
-  if(load == 0) write(rn, Half, r(d));
+  if(l == 1) r(d) = load(rn, Half);
+  if(l == 0) store(rn, Half, r(d));
   if(pre == 0) rn = up ? rn + rm : rn - rm;
 
   if(pre == 0 || writeback == 1) r(n) = rn;
@@ -247,7 +248,7 @@ void ARM::arm_op_move_half_immediate() {
   uint1 pre = instruction() >> 24;
   uint1 up = instruction() >> 23;
   uint1 writeback = instruction() >> 21;
-  uint1 load = instruction() >> 20;
+  uint1 l = instruction() >> 20;
   uint4 n = instruction() >> 16;
   uint4 d = instruction() >> 12;
   uint4 ih = instruction() >> 8;
@@ -257,8 +258,8 @@ void ARM::arm_op_move_half_immediate() {
   uint8 immediate = (ih << 4) + (il << 0);
 
   if(pre == 1) rn = up ? rn + immediate : rn - immediate;
-  if(load == 1) r(d) = read(rn, Half);
-  if(load == 0) write(rn, Half, r(d));
+  if(l == 1) r(d) = load(rn, Half);
+  if(l == 0) store(rn, Half, r(d));
   if(pre == 0) rn = up ? rn + immediate : rn - immediate;
 
   if(pre == 0 || writeback == 1) r(n) = rn;
@@ -288,7 +289,7 @@ void ARM::arm_op_load_register() {
   uint32 rm = r(m);
 
   if(pre == 1) rn = up ? rn + rm : rn - rm;
-  uint32 word = read(rn, half ? Half : Byte);
+  uint32 word = load(rn, half ? Half : Byte);
   r(d) = half ? (int16)word : (int8)word;
   if(pre == 0) rn = up ? rn + rm : rn - rm;
 
@@ -321,7 +322,7 @@ void ARM::arm_op_load_immediate() {
   uint8 immediate = (ih << 4) + (il << 0);
 
   if(pre == 1) rn = up ? rn + immediate : rn - immediate;
-  uint32 word = read(rn, half ? Half : Byte);
+  uint32 word = load(rn, half ? Half : Byte);
   r(d) = half ? (int16)word : (int8)word;
   if(pre == 0) rn = up ? rn + immediate : rn - immediate;
 
@@ -486,7 +487,7 @@ void ARM::arm_op_move_immediate_offset() {
   uint1 up = instruction() >> 23;
   uint1 byte = instruction() >> 22;
   uint1 writeback = instruction() >> 21;
-  uint1 load = instruction() >> 20;
+  uint1 l = instruction() >> 20;
   uint4 n = instruction() >> 16;
   uint4 d = instruction() >> 12;
   uint12 rm = instruction();
@@ -495,8 +496,8 @@ void ARM::arm_op_move_immediate_offset() {
   auto &rd = r(d);
 
   if(pre == 1) rn = up ? rn + rm : rn - rm;
-  if(load == 1) rd = read(rn, byte ? Byte : Word);
-  if(load == 0) write(rn, byte ? Byte : Word, rd);
+  if(l == 1) rd = load(rn, byte ? Byte : Word);
+  if(l == 0) store(rn, byte ? Byte : Word, rd);
   if(pre == 0) rn = up ? rn + rm : rn - rm;
 
   if(pre == 0 || writeback == 1) r(n) = rn;
@@ -521,7 +522,7 @@ void ARM::arm_op_move_register_offset() {
   uint1 up = instruction() >> 23;
   uint1 byte = instruction() >> 22;
   uint1 writeback = instruction() >> 21;
-  uint1 load = instruction() >> 20;
+  uint1 l = instruction() >> 20;
   uint4 n = instruction() >> 16;
   uint4 d = instruction() >> 12;
   uint5 immediate = instruction() >> 7;
@@ -540,8 +541,8 @@ void ARM::arm_op_move_register_offset() {
   if(mode == 3) rm = rs ? ror(rm, rs) : rrx(rm);
 
   if(pre == 1) rn = up ? rn + rm : rn - rm;
-  if(load == 1) rd = read(rn, byte ? Byte : Word);
-  if(load == 0) write(rn, byte ? Byte : Word, rd);
+  if(l == 1) rd = load(rn, byte ? Byte : Word);
+  if(l == 0) store(rn, byte ? Byte : Word, rd);
   if(pre == 0) rn = up ? rn + rm : rn - rm;
 
   if(pre == 0 || writeback == 1) r(n) = rn;
@@ -562,7 +563,7 @@ void ARM::arm_op_move_multiple() {
   uint1 up = instruction() >> 23;
   uint1 s = instruction() >> 22;
   uint1 writeback = instruction() >> 21;
-  uint1 load = instruction() >> 20;
+  uint1 l = instruction() >> 20;
   uint4 n = instruction() >> 16;
   uint16 list = instruction();
 
@@ -574,25 +575,29 @@ void ARM::arm_op_move_multiple() {
 
   Processor::Mode pmode = mode();
   bool usr = false;
-  if(s && load == 1 && (list & 0x8000) == 0) usr = true;
-  if(s && load == 0) usr = true;
+  if(s && l == 1 && (list & 0x8000) == 0) usr = true;
+  if(s && l == 0) usr = true;
 
   if(usr) processor.setMode(Processor::Mode::USR);
 
-  for(unsigned n = 0; n < 16; n++) {
-    if(list & (1 << n)) {
-      if(load == 1) r(n) = read(rn, Word);
-      if(load == 0) write(rn, Word, r(n));
+  sequential() = false;
+  for(unsigned m = 0; m < 16; m++) {
+    if(list & (1 << m)) {
+      if(l == 1) r(m) = read(rn, Word);
+      if(l == 0) write(rn, Word, r(m));
       rn += 4;
     }
   }
 
   if(usr) processor.setMode(pmode);
 
-  if(load == 1 && s && (list & 0x8000)) {
-    if(mode() != Processor::Mode::USR && mode() != Processor::Mode::SYS) {
-      cpsr() = spsr();
-      processor.setMode((Processor::Mode)cpsr().m);
+  if(l == 1) {
+    idle();
+    if(s && (list & 0x8000)) {
+      if(mode() != Processor::Mode::USR && mode() != Processor::Mode::SYS) {
+        cpsr() = spsr();
+        processor.setMode((Processor::Mode)cpsr().m);
+      }
     }
   }
 
diff --git a/bsnes/processor/arm/instructions-thumb.cpp b/bsnes/processor/arm/instructions-thumb.cpp
index c56ff088..b795d4cd 100755
--- a/bsnes/processor/arm/instructions-thumb.cpp
+++ b/bsnes/processor/arm/instructions-thumb.cpp
@@ -5,6 +5,7 @@ void ARM::thumb_step() {
     pipeline.reload = false;
     r(15).data &= ~1;
 
+    sequential() = false;
     pipeline.fetch.address = r(15) & ~1;
     pipeline.fetch.instruction = read(pipeline.fetch.address, Half);
 
@@ -62,12 +63,12 @@ void ARM::thumb_opcode(uint4 opcode, uint4 d, uint4 m) {
   switch(opcode) {
   case  0: r(d) = bit(r(d) & r(m));          break;  //AND
   case  1: r(d) = bit(r(d) ^ r(m));          break;  //EOR
-  case  2: r(d) = lsl(r(d), r(m) & 0xff);    break;  //LSL
-  case  3: r(d) = lsr(r(d), r(m) & 0xff);    break;  //LSR
-  case  4: r(d) = asr(r(d), r(m) & 0xff);    break;  //ASR
+  case  2: r(d) = bit(lsl(r(d), r(m)));      break;  //LSL
+  case  3: r(d) = bit(lsr(r(d), r(m)));      break;  //LSR
+  case  4: r(d) = bit(asr(r(d), r(m)));      break;  //ASR
   case  5: r(d) = add(r(d), r(m), cpsr().c); break;  //ADC
   case  6: r(d) = sub(r(d), r(m), cpsr().c); break;  //SBC
-  case  7: r(d) = ror(r(d), r(m) & 0xff);    break;  //ROR
+  case  7: r(d) = bit(ror(r(d), r(m)));      break;  //ROR
   case  8:        bit(r(d) & r(m));          break;  //TST
   case  9: r(d) = sub(0, r(m), 1);           break;  //NEG
   case 10:        sub(r(d), r(m), 1);        break;  //CMP
@@ -128,9 +129,9 @@ void ARM::thumb_op_shift_immediate() {
   uint3 d = instruction() >> 0;
 
   switch(opcode) {
-  case 0: r(d) = lsl(r(m), immediate); break;
-  case 1: r(d) = lsr(r(m), immediate == 0 ? 32u : (unsigned)immediate); break;
-  case 2: r(d) = asr(r(m), immediate == 0 ? 32u : (unsigned)immediate); break;
+  case 0: r(d) = bit(lsl(r(m), immediate)); break;
+  case 1: r(d) = bit(lsr(r(m), immediate == 0 ? 32u : (unsigned)immediate)); break;
+  case 2: r(d) = bit(asr(r(m), immediate == 0 ? 32u : (unsigned)immediate)); break;
   }
 }
 
@@ -203,7 +204,7 @@ void ARM::thumb_op_load_literal() {
   uint8 displacement = instruction();
 
   unsigned rm = (r(15) & ~3) + displacement * 4;
-  r(d) = read(rm, Word);
+  r(d) = load(rm, Word);
 }
 
 //(ld(r,s),str){b,h} rd,[rn,rm]
@@ -219,14 +220,14 @@ void ARM::thumb_op_move_register_offset() {
   uint3 d = instruction() >> 0;
 
   switch(opcode) {
-  case 0: write(r(n) + r(m), Word, r(d));        break;  //STR
-  case 1: write(r(n) + r(m), Half, r(d));        break;  //STRH
-  case 2: write(r(n) + r(m), Byte, r(d));        break;  //STRB
-  case 3: r(d) = (int8)read(r(n) + r(m), Byte);  break;  //LDSB
-  case 4: r(d) = read(r(n) + r(m), Word);        break;  //LDR
-  case 5: r(d) = read(r(n) + r(m), Half);        break;  //LDRH
-  case 6: r(d) = read(r(n) + r(m), Byte);        break;  //LDRB
-  case 7: r(d) = (int16)read(r(n) + r(m), Half); break;  //LDSH
+  case 0: store(r(n) + r(m), Word, r(d));        break;  //STR
+  case 1: store(r(n) + r(m), Half, r(d));        break;  //STRH
+  case 2: store(r(n) + r(m), Byte, r(d));        break;  //STRB
+  case 3: r(d) =  (int8)load(r(n) + r(m), Byte); break;  //LDSB
+  case 4: r(d) = load(r(n) + r(m), Word);        break;  //LDR
+  case 5: r(d) = load(r(n) + r(m), Half);        break;  //LDRH
+  case 6: r(d) = load(r(n) + r(m), Byte);        break;  //LDRB
+  case 7: r(d) = (int16)load(r(n) + r(m), Half); break;  //LDSH
   }
 }
 
@@ -237,13 +238,13 @@ void ARM::thumb_op_move_register_offset() {
 //n = rn
 //d = rd
 void ARM::thumb_op_move_word_immediate() {
-  uint1 load = instruction() >> 11;
+  uint1 l = instruction() >> 11;
   uint5 offset = instruction() >> 6;
   uint3 n = instruction() >> 3;
   uint3 d = instruction() >> 0;
 
-  if(load == 1) r(d) = read(r(n) + offset * 4, Word);
-  if(load == 0) write(r(n) + offset * 4, Word, r(d));
+  if(l == 1) r(d) = load(r(n) + offset * 4, Word);
+  if(l == 0) store(r(n) + offset * 4, Word, r(d));
 }
 
 //(ldr,str)b rd,[rn,#offset]
@@ -253,13 +254,13 @@ void ARM::thumb_op_move_word_immediate() {
 //n = rn
 //d = rd
 void ARM::thumb_op_move_byte_immediate() {
-  uint1 load = instruction() >> 11;
+  uint1 l = instruction() >> 11;
   uint5 offset = instruction() >> 6;
   uint3 n = instruction() >> 3;
   uint3 d = instruction() >> 0;
 
-  if(load == 1) r(d) = read(r(n) + offset, Byte);
-  if(load == 0) write(r(n) + offset, Byte, r(d));
+  if(l == 1) r(d) = load(r(n) + offset, Byte);
+  if(l == 0) store(r(n) + offset, Byte, r(d));
 }
 
 //(ldr,str)h rd,[rn,#offset]
@@ -269,27 +270,27 @@ void ARM::thumb_op_move_byte_immediate() {
 //n = rn
 //d = rd
 void ARM::thumb_op_move_half_immediate() {
-  uint1 load = instruction() >> 11;
+  uint1 l = instruction() >> 11;
   uint5 offset = instruction() >> 6;
   uint3 n = instruction() >> 3;
   uint3 d = instruction() >> 0;
 
-  if(load == 1) r(d) = read(r(n) + offset * 2, Half);
-  if(load == 0) write(r(n) + offset * 2, Half, r(d));
+  if(l == 1) r(d) = load(r(n) + offset * 2, Half);
+  if(l == 0) store(r(n) + offset * 2, Half, r(d));
 }
 
 //(ldr,str) rd,[sp,#immediate]
 //1001 oddd iiii iiii
-//o = opcode
+//l = load
 //d = rd
 //i = immediate
 void ARM::thumb_op_move_stack() {
-  uint1 opcode = instruction() >> 11;
+  uint1 l = instruction() >> 11;
   uint3 d = instruction() >> 8;
   uint8 immediate = instruction();
 
-  if(opcode == 0) write(r(13) + immediate * 4, Word, r(d));
-  if(opcode == 1) r(d) = read(r(13) + immediate * 4, Word);
+  if(l == 1) r(d) = load(r(13) + immediate * 4, Word);
+  if(l == 0) store(r(13) + immediate * 4, Word, r(d));
 }
 
 //add rd,{pc,sp},#immediate
@@ -325,31 +326,33 @@ void ARM::thumb_op_adjust_stack() {
 //r = push lr -or- pop pc
 //l = register list
 void ARM::thumb_op_stack_multiple() {
-  uint1 load = instruction() >> 11;
+  uint1 l = instruction() >> 11;
   uint1 branch = instruction() >> 8;
   uint8 list = instruction();
 
   uint32 sp = 0;
-  if(load == 1) sp = r(13);
-  if(load == 0) sp = r(13) - (bit::count(list) + branch) * 4;
+  if(l == 1) sp = r(13);
+  if(l == 0) sp = r(13) - (bit::count(list) + branch) * 4;
 
-  for(unsigned l = 0; l < 8; l++) {
-    if(list & (1 << l)) {
-      if(load == 1) r(l) = read(sp, Word);  //POP
-      if(load == 0) write(sp, Word, r(l));  //PUSH
+  sequential() = false;
+  for(unsigned m = 0; m < 8; m++) {
+    if(list & (1 << m)) {
+      if(l == 1) r(m) = read(sp, Word);  //POP
+      if(l == 0) write(sp, Word, r(m));  //PUSH
       sp += 4;
     }
   }
 
   if(branch) {
     //note: ARMv5+ POP sets cpsr().t
-    if(load == 1) r(15) = read(sp, Word);  //POP
-    if(load == 0) write(sp, Word, r(14));  //PUSH
+    if(l == 1) r(15) = read(sp, Word);  //POP
+    if(l == 0) write(sp, Word, r(14));  //PUSH
     sp += 4;
   }
 
-  if(load == 1) r(13) += (bit::count(list) + branch) * 4;
-  if(load == 0) r(13) -= (bit::count(list) + branch) * 4;
+  if(l == 1) idle();
+  if(l == 1) r(13) += (bit::count(list) + branch) * 4;
+  if(l == 0) r(13) -= (bit::count(list) + branch) * 4;
 }
 
 //(ldmia,stmia) rn!,{r...}
@@ -358,17 +361,20 @@ void ARM::thumb_op_stack_multiple() {
 //n = rn
 //l = register list
 void ARM::thumb_op_move_multiple() {
-  uint1 load = instruction() >> 11;
+  uint1 l = instruction() >> 11;
   uint3 n = instruction() >> 8;
   uint8 list = instruction();
 
-  for(unsigned l = 0; l < 8; l++) {
-    if(list & (1 << l)) {
-      if(load == 1) r(l) = read(r(n), Word);  //LDMIA
-      if(load == 0) write(r(n), Word, r(l));  //STMIA
+  sequential() = false;
+  for(unsigned m = 0; m < 8; m++) {
+    if(list & (1 << m)) {
+      if(l == 1) r(m) = read(r(n), Word);  //LDMIA
+      if(l == 0) write(r(n), Word, r(m));  //STMIA
       r(n) += 4;
     }
   }
+
+  if(l == 1) idle();
 }
 
 //swi #immediate
diff --git a/bsnes/processor/arm/registers.cpp b/bsnes/processor/arm/registers.cpp
index 9292be3f..e6a3539d 100755
--- a/bsnes/processor/arm/registers.cpp
+++ b/bsnes/processor/arm/registers.cpp
@@ -11,6 +11,7 @@ void ARM::Processor::power() {
   pc = 0;
 
   carryout = false;
+  sequential = false;
   irqline = false;
 
   cpsr = 0;
diff --git a/bsnes/processor/arm/registers.hpp b/bsnes/processor/arm/registers.hpp
index c5f355b8..6c1fa426 100755
--- a/bsnes/processor/arm/registers.hpp
+++ b/bsnes/processor/arm/registers.hpp
@@ -104,6 +104,7 @@ struct Processor {
   GPR pc;
   PSR cpsr;
   bool carryout;
+  bool sequential;
   bool irqline;
 
   GPR *r[16];
@@ -123,6 +124,7 @@ alwaysinline GPR& r(unsigned n) { return *processor.r[n]; }
 alwaysinline PSR& cpsr() { return processor.cpsr; }
 alwaysinline PSR& spsr() { return *processor.spsr; }
 alwaysinline bool& carryout() { return processor.carryout; }
+alwaysinline bool& sequential() { return processor.sequential; }
 alwaysinline uint32 instruction() { return pipeline.execute.instruction; }
 alwaysinline Processor::Mode mode() { return (Processor::Mode)processor.cpsr.m; }
 alwaysinline bool privilegedmode() const { return (Processor::Mode)processor.cpsr.m != Processor::Mode::USR; }
diff --git a/bsnes/snes/chip/armdsp/armdsp.hpp b/bsnes/snes/chip/armdsp/armdsp.hpp
index e6bad18a..385cfc47 100755
--- a/bsnes/snes/chip/armdsp/armdsp.hpp
+++ b/bsnes/snes/chip/armdsp/armdsp.hpp
@@ -12,6 +12,7 @@ struct ArmDSP : Processor::ARM, public Coprocessor {
   void enter();
 
   void step(unsigned clocks);
+  void bus_idle(uint32 addr);
   uint32 bus_read(uint32 addr, uint32 size);
   void bus_write(uint32 addr, uint32 size, uint32 word);
 
diff --git a/bsnes/snes/chip/armdsp/memory.cpp b/bsnes/snes/chip/armdsp/memory.cpp
index f1e5ce11..29af732c 100755
--- a/bsnes/snes/chip/armdsp/memory.cpp
+++ b/bsnes/snes/chip/armdsp/memory.cpp
@@ -1,6 +1,12 @@
 #ifdef ARMDSP_CPP
 
+void ArmDSP::bus_idle(uint32 addr) {
+  step(1);
+}
+
 uint32 ArmDSP::bus_read(uint32 addr, uint32 size) {
+  step(1);
+
   static auto memory = [&](const uint8 *memory, uint32 addr, uint32 size) {
     memory += addr & ~3;
     return (memory[0] << 0) | (memory[1] << 8) | (memory[2] << 16) | (memory[3] << 24);
@@ -34,6 +40,8 @@ uint32 ArmDSP::bus_read(uint32 addr, uint32 size) {
 }
 
 void ArmDSP::bus_write(uint32 addr, uint32 size, uint32 word) {
+  step(1);
+
   static auto memory = [](uint8 *memory, uint32 addr, uint32 size, uint32 word) {
     switch(size) {
     case Word:
diff --git a/bsnes/target-ui/Makefile b/bsnes/target-ui/Makefile
index 285b9f39..34fc9ab9 100755
--- a/bsnes/target-ui/Makefile
+++ b/bsnes/target-ui/Makefile
@@ -69,18 +69,23 @@ else
 endif
 
 install:
-ifeq ($(platform),x)
-	install -D -m 755 out/$(name) $(DESTDIR)$(prefix)/bin/$(name)
+ifeq ($(USER),root)
+	@echo Please do not run make install as root.
+	@echo The installer needs to know your home directory to install important files.
+else ifeq ($(platform),x)
+	sudo install -D -m 755 out/$(name) $(DESTDIR)$(prefix)/bin/$(name)
+	sudo install -D -m 644 data/$(name).png $(DESTDIR)$(prefix)/share/pixmaps/$(name).png
+	sudo install -D -m 644 data/$(name).desktop $(DESTDIR)$(prefix)/share/applications/$(name).desktop
+
 	mkdir -p ~/.config/$(name)
-	install -D -m 644 data/$(name).png $(DESTDIR)$(prefix)/share/pixmaps/$(name).png
-	install -D -m 644 data/$(name).desktop $(DESTDIR)$(prefix)/share/applications/$(name).desktop
 	cp data/cheats.xml ~/.config/$(name)/cheats.xml
-	chmod 777 ~/.config/$(name) ~/.config/$(name)/cheats.xml
+	cp -R data/GBA.system ~/.config/$(name)
+	chmod -R 777 ~/.config/$(name)
 endif
 
 uninstall:
 ifeq ($(platform),x)
-	rm $(DESTDIR)$(prefix)/bin/$(name)
-	rm $(DESTDIR)$(prefix)/share/pixmaps/$(name).png
-	rm $(DESTDIR)$(prefix)/share/applications/$(name).desktop
+	sudo rm $(DESTDIR)$(prefix)/bin/$(name)
+	sudo rm $(DESTDIR)$(prefix)/share/pixmaps/$(name).png
+	sudo rm $(DESTDIR)$(prefix)/share/applications/$(name).desktop
 endif
diff --git a/bsnes/target-ui/interface/gba/gba.cpp b/bsnes/target-ui/interface/gba/gba.cpp
index 11ae4c98..5f590113 100755
--- a/bsnes/target-ui/interface/gba/gba.cpp
+++ b/bsnes/target-ui/interface/gba/gba.cpp
@@ -1,4 +1,25 @@
 void InterfaceGBA::initialize() {
+  string filename = application->path("GBA.system/manifest.xml");
+  string markup;
+  markup.readfile(filename);
+  XML::Document document(markup);
+
+  if(document["system"]["bios"].exists()) {
+    auto &bios = document["system"]["bios"];
+    string firmware = bios["firmware"].data;
+    string hash = bios["sha256"].data;
+
+    uint8_t *data;
+    unsigned size;
+    if(file::read({dir(filename),firmware}, data, size) == true) {
+      if(nall::sha256(data, size) == hash) {
+        GBA::bios.load(data, size);
+      } else {
+        MessageWindow::information(Window::None, "Warning: GBA BIOS SHA256 sum is incorrect.");
+      }
+    }
+  }
+
   GBA::interface = this;
   GBA::system.init();
 }
@@ -10,42 +31,27 @@ bool InterfaceGBA::cartridgeLoaded() {
 bool InterfaceGBA::loadCartridge(const string &filename) {
   interface->unloadCartridge();
 
-  uint8_t *biosdata;
-  unsigned biossize;
-
-  uint8_t *cartdata;
-  unsigned cartsize;
+  uint8_t *data;
+  unsigned size;
 
   if(filename.endswith("/")) {
-    if(file::exists({filename, "bios.rom"}) == false) {
-      message("Error: Game Boy Advance BIOS (bios.rom) not found.");
-      return false;
-    }
-    if(file::read({filename, "bios.rom"}, biosdata, biossize) == false) return false;
-    if(file::read({filename, "program.rom"}, cartdata, cartsize) == false) return false;
+    if(file::read({filename, "program.rom"}, data, size) == false) return false;
     interface->base = {true, filename};
   } else {
-    if(file::exists({dir(filename), "gbabios.rom"}) == false) {
-      message("Error: Game Boy Advance BIOS (gbabios.rom) not found.");
-      return false;
-    }
-    if(file::read({dir(filename), "gbabios.rom"}, biosdata, biossize) == false) return false;
-    if(file::read(filename, cartdata, cartsize) == false) return false;
+    if(file::read(filename, data, size) == false) return false;
     interface->base = {false, filename};
   }
 
   interface->game = interface->base;
   interface->cartridgeTitle = interface->base.title();
-  interface->applyPatch(interface->base, cartdata, cartsize);
+  interface->applyPatch(interface->base, data, size);
 
   string markup;
   markup.readfile(interface->base.filename("manifest.xml", ".xml"));
 
-  GBA::bios.load(biosdata, biossize);
-  GBA::cartridge.load(markup, cartdata, cartsize);
+  GBA::cartridge.load(markup, data, size);
   GBA::system.power();
-  delete[] biosdata;
-  delete[] cartdata;
+  delete[] data;
 
   GBA::video.generate(GBA::Video::Format::RGB30);
   interface->loadCartridge(::Interface::Mode::GBA);
diff --git a/bsnes/target-ui/settings/advanced.cpp b/bsnes/target-ui/settings/advanced.cpp
index f3c0b4c5..cf43888e 100755
--- a/bsnes/target-ui/settings/advanced.cpp
+++ b/bsnes/target-ui/settings/advanced.cpp
@@ -15,8 +15,6 @@ AdvancedSettings::AdvancedSettings() {
   focusPolicy[2].setText("Pause emulation");
   RadioBox::group(focusPolicy[0], focusPolicy[1], focusPolicy[2]);
   focusPolicy[config->input.focusPolicy].setChecked();
-  aboutLabel.setFont(application->boldFont);
-  aboutLabel.setText("bsnes    author: byuu    license: GPLv3    website: byuu.org");
 
   lstring list;
 
@@ -55,8 +53,6 @@ AdvancedSettings::AdvancedSettings() {
     focusPolicyLayout.append(focusPolicy[0], { ~0,  0 }, 5);
     focusPolicyLayout.append(focusPolicy[1], { ~0,  0 }, 5);
     focusPolicyLayout.append(focusPolicy[2], { ~0,  0 }, 0);
-  append(spacer,                             { ~0, ~0 }, 0);
-  append(aboutLabel,                         { ~0,  0 }, 0);
 
   videoDriver.onChange = [&] {
     lstring list;
diff --git a/bsnes/target-ui/settings/advanced.hpp b/bsnes/target-ui/settings/advanced.hpp
index 89e0432e..860527d8 100755
--- a/bsnes/target-ui/settings/advanced.hpp
+++ b/bsnes/target-ui/settings/advanced.hpp
@@ -11,8 +11,6 @@ struct AdvancedSettings : SettingsLayout {
   Label focusPolicyLabel;
   HorizontalLayout focusPolicyLayout;
     RadioBox focusPolicy[3];
-  Widget spacer;
-  Label aboutLabel;
 
   AdvancedSettings();
 };