diff --git a/.gitignore b/.gitignore
index 2d8bd687..810f048f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,4 +9,6 @@ roms/
 .cache/
 .vscode/
 vgcore.*
-*.data
\ No newline at end of file
+*.data
+disasm.txt
+log.txt
\ No newline at end of file
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 1c779575..88cd84f1 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -13,6 +13,15 @@ find_package(fmt REQUIRED)
 
 add_executable(natsukashii main.cpp)
 
+if (CMAKE_BUILD_TYPE MATCHES Debug)
+  set(OPTIMIZATIONS -g
+    #-fsanitize=address -fsanitize=undefined
+    )
+  #target_link_libraries(natsukashii PUBLIC -fsanitize=address -fsanitize=undefined)
+elseif(CMAKE_BUILD_TYPE MATCHES Release)
+  set(OPTIMIZATIONS -O3)
+endif()
+
 target_link_libraries(natsukashii PUBLIC frontend n64 fmt)
 target_include_directories(natsukashii PUBLIC . ../external)
-target_compile_options(natsukashii PUBLIC -Wpedantic -Wimplicit-fallthrough -Wextra -Wall)
+target_compile_options(natsukashii PUBLIC ${OPTIMIZATIONS} -Wpedantic -Wimplicit-fallthrough -Wextra -Wall)
diff --git a/src/n64/Core.cpp b/src/n64/Core.cpp
index a3bf3d0a..29a21dd4 100644
--- a/src/n64/Core.cpp
+++ b/src/n64/Core.cpp
@@ -43,6 +43,8 @@ void Core::Run(Window& window) {
     int frameCycles = 0;
     if(!pause && romLoaded) {
       for (int i = 0; i < mmio.vi.numHalflines; i++) {
+        mmio.vi.current = (i << 1) + field;
+
         if ((mmio.vi.current & 0x3FE) == mmio.vi.intr) {
           InterruptRaise(mmio.mi, cpu.regs, Interrupt::VI);
         }
@@ -54,7 +56,7 @@ void Core::Run(Window& window) {
           mmio.rsp.Step(mmio.mi, cpu.regs, mmio.rdp);
           mmio.rsp.Step(mmio.mi, cpu.regs, mmio.rdp);
 
-          mmio.ai.Step(mem, cpu.regs, 1);
+          //mmio.ai.Step(mem, cpu.regs, 1);
         }
 
         cycles -= mmio.vi.cyclesPerHalfline;
@@ -67,7 +69,7 @@ void Core::Run(Window& window) {
       UpdateScreenParallelRdp(*this, window, GetVI());
 
       int missedCycles = N64_CYCLES_PER_FRAME - frameCycles;
-      mmio.ai.Step(mem, cpu.regs, missedCycles);
+      //mmio.ai.Step(mem, cpu.regs, missedCycles);
     } else if(pause && romLoaded) {
       UpdateScreenParallelRdp(*this, window, GetVI());
     } else if(pause && !romLoaded) {
diff --git a/src/n64/core/Audio.cpp b/src/n64/core/Audio.cpp
index b3ffaa8d..15e10f3d 100644
--- a/src/n64/core/Audio.cpp
+++ b/src/n64/core/Audio.cpp
@@ -2,7 +2,7 @@
 #include <SDL2/SDL.h>
 #include "util.hpp"
 
-namespace natsukashii::core {
+namespace n64 {
 #define AUDIO_SAMPLE_RATE 48000
 #define SYSTEM_SAMPLE_FORMAT AUDIO_F32SYS
 #define SYSTEM_SAMPLE_SIZE 4
diff --git a/src/n64/core/Audio.hpp b/src/n64/core/Audio.hpp
index 3bf44e64..e3878ec0 100644
--- a/src/n64/core/Audio.hpp
+++ b/src/n64/core/Audio.hpp
@@ -1,7 +1,7 @@
 #pragma once
 #include "common.hpp"
 
-namespace natsukashii::core {
+namespace n64 {
 void PushSample(s16, s16);
 void InitAudio();
 void AdjustSampleRate(int);
diff --git a/src/n64/core/Cpu.cpp b/src/n64/core/Cpu.cpp
index 7d128a2f..46e9fc27 100644
--- a/src/n64/core/Cpu.cpp
+++ b/src/n64/core/Cpu.cpp
@@ -41,17 +41,17 @@ void FireException(Registers& regs, ExceptionCode code, int cop, s64 pc) {
   bool old_exl = regs.cop0.status.exl;
 
   if(!regs.cop0.status.exl) {
-    if(regs.prevDelaySlot) { // TODO: cached value of delay_slot should be used, but Namco Museum breaks!
+    if(regs.delaySlot) { // TODO: cached value of delay_slot should be used, but Namco Museum breaks!
       regs.cop0.cause.branchDelay = true;
       pc -= 4;
     } else {
       regs.cop0.cause.branchDelay = false;
     }
 
+    regs.cop0.status.exl = true;
     regs.cop0.EPC = pc;
   }
 
-  regs.cop0.status.exl = true;
   regs.cop0.cause.copError = cop;
   regs.cop0.cause.exceptionCode = code;
 
@@ -59,12 +59,8 @@ void FireException(Registers& regs, ExceptionCode code, int cop, s64 pc) {
     util::panic("BEV bit set!\n");
   } else {
     switch(code) {
-      case Interrupt: case TLBModification:
-      case AddressErrorLoad: case AddressErrorStore:
-      case InstructionBusError: case DataBusError:
-      case Syscall: case Breakpoint:
-      case ReservedInstruction: case CoprocessorUnusable:
-      case Overflow: case Trap:
+      case Interrupt ... TLBModification:
+      case AddressErrorLoad ... Trap:
       case FloatingPointError: case Watch:
         regs.SetPC(s64(s32(0x80000180)));
         break;
@@ -91,14 +87,28 @@ inline void HandleInterrupt(Registers& regs) {
 void Cpu::Step(Mem& mem) {
   regs.gpr[0] = 0;
 
+  CheckCompareInterrupt(mem.mmio.mi, regs);
+  HandleInterrupt(regs);
+
   regs.prevDelaySlot = regs.delaySlot;
   regs.delaySlot = false;
 
-  CheckCompareInterrupt(mem.mmio.mi, regs);
-
   u32 instruction = mem.Read<u32>(regs, regs.pc, regs.pc);
 
-  HandleInterrupt(regs);
+  /*cs_insn* insn;
+  u8 code[4]{};
+  memcpy(code, &instruction, 4);
+
+  u32 pc = regs.pc;
+
+  size_t count = cs_disasm(handle, code, 4, (u64)pc, 0, &insn);
+  if(count > 0) {
+    for(int i = 0; i < count; i++) {
+      fprintf(log, "%s", fmt::format("0x{:016X}\t{}\t{}\n", insn[i].address, insn[i].mnemonic, insn[i].op_str).c_str());
+    }
+
+    cs_free(insn, count);
+  }*/
 
   regs.oldPC = regs.pc;
   regs.pc = regs.nextPC;
diff --git a/src/n64/core/Cpu.hpp b/src/n64/core/Cpu.hpp
index 0222d93a..56e3a24b 100644
--- a/src/n64/core/Cpu.hpp
+++ b/src/n64/core/Cpu.hpp
@@ -6,12 +6,24 @@
 
 namespace n64 {
 struct Cpu {
-  Cpu() { Reset(); }
-  ~Cpu() = default;
+  Cpu() {
+    log = fopen("disasm.txt", "w");
+    if(cs_open(CS_ARCH_MIPS, CS_MODE_MIPS64, &handle) != CS_ERR_OK) {
+      util::panic("Could not initialize capstone!\n");
+    }
+    Reset();
+  }
+
+  ~Cpu() {
+    fclose(log);
+    cs_close(&handle);
+  }
   void Reset();
   void Step(Mem&);
   Registers regs;
 private:
+  csh handle;
+  FILE* log;
   friend struct Cop1;
 
   void special(Mem&, u32);
diff --git a/src/n64/core/RSP.cpp b/src/n64/core/RSP.cpp
index 8670753d..3b6f8234 100644
--- a/src/n64/core/RSP.cpp
+++ b/src/n64/core/RSP.cpp
@@ -31,13 +31,12 @@ void RSP::Reset() {
 
 void RSP::Step(MI& mi, Registers& regs, RDP& rdp) {
   if(!spStatus.halt) {
-    util::panic("RSP!\n");
-   //gpr[0] = 0;
-   //u32 instr = util::ReadAccess<u32>(imem, pc & IMEM_DSIZE);
-   //oldPC = pc & 0xFFF;
-   //pc = nextPC & 0xFFF;
-   //nextPC += 4;
-   //Exec(mi, regs, rdp, instr);
+   gpr[0] = 0;
+   u32 instr = util::ReadAccess<u32>(imem, pc & IMEM_DSIZE);
+   oldPC = pc & 0xFFF;
+   pc = nextPC & 0xFFF;
+   nextPC += 4;
+   Exec(mi, regs, rdp, instr);
   }
 }
 
diff --git a/src/n64/core/cpu/instructions.cpp b/src/n64/core/cpu/instructions.cpp
index 07c602f0..ea1e8a8d 100644
--- a/src/n64/core/cpu/instructions.cpp
+++ b/src/n64/core/cpu/instructions.cpp
@@ -137,7 +137,7 @@ void Cpu::branch_likely(bool cond, s64 address) {
   if (cond) {
     regs.nextPC = address;
   } else {
-    regs.SetPC(regs.pc + 4);
+    regs.SetPC(regs.nextPC);
   }
 }
 
@@ -580,7 +580,7 @@ void Cpu::dsra32(u32 instr) {
 void Cpu::jr(u32 instr) {
   s32 address = regs.gpr[RS(instr)];
   if ((address & 3) != 0) {
-    HandleTLBException(regs, (s64)((s32)address));
+    HandleTLBException(regs, address);
     FireException(regs, ExceptionCode::AddressErrorStore, 0, regs.oldPC);
   }
 
diff --git a/src/n64/core/cpu/registers/Cop0.cpp b/src/n64/core/cpu/registers/Cop0.cpp
index 0d9721d3..68ff10a7 100644
--- a/src/n64/core/cpu/registers/Cop0.cpp
+++ b/src/n64/core/cpu/registers/Cop0.cpp
@@ -11,7 +11,9 @@ Cop0::Cop0() {
 void Cop0::Reset() {
   cause.raw = 0xB000007C;
   status.raw = 0x241000E0;
-  PRId = 0x00000B22;
+  wired = 64;
+  index = 64;
+  PRId = 0x00000B00;
   Config = 0x7006E463;
   EPC = 0xFFFFFFFFFFFFFFFF;
   ErrorEPC = 0xFFFFFFFFFFFFFFFF;
@@ -54,17 +56,17 @@ u32 Cop0::GetReg32(u8 addr) {
 
 u64 Cop0::GetReg64(u8 addr) {
   switch(addr) {
-    case 2: return entryLo0.raw;
-    case 3: return entryLo1.raw;
-    case 4: return context.raw;
-    case 8: return badVaddr;
-    case 10: return entryHi.raw;
-    case 12: return status.raw;
-    case 14: return EPC;
-    case 15: return PRId;
-    case 17: return LLAddr;
-    case 20: return xcontext.raw & 0xFFFFFFFFFFFFFFF0;
-    case 30: return ErrorEPC;
+    case COP0_REG_ENTRYLO0: return entryLo0.raw;
+    case COP0_REG_ENTRYLO1: return entryLo1.raw;
+    case COP0_REG_CONTEXT: return context.raw;
+    case COP0_REG_BADVADDR: return badVaddr;
+    case COP0_REG_ENTRYHI: return entryHi.raw;
+    case COP0_REG_STATUS: return status.raw;
+    case COP0_REG_EPC: return EPC;
+    case COP0_REG_PRID: return PRId;
+    case COP0_REG_LLADDR: return LLAddr;
+    case COP0_REG_XCONTEXT: return xcontext.raw & 0xFFFFFFFFFFFFFFF0;
+    case COP0_REG_ERROREPC: return ErrorEPC;
     default:
       util::panic("Unsupported word read from COP0 register {}\n", index);
   }
@@ -104,7 +106,9 @@ void Cop0::SetReg32(u8 addr, u32 value) {
       cause.ip0 = temp.ip0;
       cause.ip1 = temp.ip1;
     } break;
-    case COP0_REG_EPC: EPC = s64(s32(value)); break;
+    case COP0_REG_EPC:
+      EPC = s64(s32(value));
+      break;
     case COP0_REG_PRID: break;
     case COP0_REG_CONFIG: {
       Config &= ~CONFIG_MASK;
@@ -121,8 +125,8 @@ void Cop0::SetReg32(u8 addr, u32 value) {
     case COP0_REG_TAGLO: TagLo = value; break;
     case COP0_REG_TAGHI: TagHi = value; break;
     case COP0_REG_ERROREPC: ErrorEPC = s64(s32(value)); break;
-    case  7: case 21: case 22: break;
-    case 23: case 24: case 25: break;
+    case  7: case 21: case 22:
+    case 23: case 24: case 25:
     case 31: break;
     default:
       util::panic("Unsupported word read from COP0 register {}\n", index);
diff --git a/src/n64/core/cpu/registers/Cop1.cpp b/src/n64/core/cpu/registers/Cop1.cpp
index 05c8b77d..f9b972ef 100644
--- a/src/n64/core/cpu/registers/Cop1.cpp
+++ b/src/n64/core/cpu/registers/Cop1.cpp
@@ -9,7 +9,7 @@ Cop1::Cop1() {
 }
 
 void Cop1::Reset() {
-  fcr0 = 0xa00;
+  fcr0 = 0;
   fcr31.raw = 0;
   memset(fgr, 0, 32 * sizeof(FGR));
 }
diff --git a/src/n64/core/mmio/AI.cpp b/src/n64/core/mmio/AI.cpp
index 695d1b00..a298bc84 100644
--- a/src/n64/core/mmio/AI.cpp
+++ b/src/n64/core/mmio/AI.cpp
@@ -10,10 +10,10 @@ void AI::Reset() {
   dacRate = 0;
   bitrate = 0;
   dmaCount = 0;
-  memset(dmaLen, 0, 2);
-  memset(dmaAddr, 0, 2);
   dmaAddrCarry = false;
   cycles = 0;
+  memset(dmaLen, 0, 2);
+  memset(dmaAddr, 0, 2);
   dac = {44100, N64_CPU_FREQ / dac.freq, 16};
 }
 
@@ -36,8 +36,6 @@ auto AI::Read(u32 addr) const -> u32 {
 
 #define max(x, y) ((x) > (y) ? (x) : (y))
 
-using namespace natsukashii::core;
-
 void AI::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
   switch(addr) {
     case 0x04500000:
diff --git a/src/n64/core/mmio/Interrupt.cpp b/src/n64/core/mmio/Interrupt.cpp
index 786e1114..7ccc1dcd 100644
--- a/src/n64/core/mmio/Interrupt.cpp
+++ b/src/n64/core/mmio/Interrupt.cpp
@@ -27,6 +27,7 @@ void InterruptRaise(MI &mi, Registers &regs, Interrupt intr) {
 
   UpdateInterrupt(mi, regs);
 }
+
 void InterruptLower(MI &mi, Registers &regs, Interrupt intr) {
   switch(intr) {
     case Interrupt::VI:
diff --git a/src/n64/core/mmio/PI.cpp b/src/n64/core/mmio/PI.cpp
index 633b3b2d..d28fb501 100644
--- a/src/n64/core/mmio/PI.cpp
+++ b/src/n64/core/mmio/PI.cpp
@@ -58,7 +58,7 @@ void PI::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
       dramAddr = dram_addr + len;
       cartAddr = cart_addr + len;
       InterruptRaise(mi, regs, Interrupt::PI);
-      status = status & 0xFFFFFFFE;
+      status &= 0xFFFFFFFE;
       util::logdebug("PI DMA from rdram to cart (size: {:.2f} MiB)\n", (float)len / 1048576);
     } break;
     case 0x0460000C: {
@@ -75,7 +75,7 @@ void PI::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
       dramAddr = dram_addr + len;
       cartAddr = cart_addr + len;
       InterruptRaise(mi, regs, Interrupt::PI);
-      status = status & 0xFFFFFFFE;
+      status &= 0xFFFFFFFE;
       util::logdebug("PI DMA from cart to rdram (size: {:.2f} MiB)\n", (float)len / 1048576);
     } break;
     case 0x04600010:
diff --git a/src/n64/core/mmio/VI.cpp b/src/n64/core/mmio/VI.cpp
index 724a1a7f..66f68c50 100644
--- a/src/n64/core/mmio/VI.cpp
+++ b/src/n64/core/mmio/VI.cpp
@@ -10,7 +10,13 @@ VI::VI () {
 }
 
 void VI::Reset() {
+  status.raw = 0xF;
   intr = 256;
+  origin = 0;
+  width = 320;
+  current = 0;
+  vsync = 0;
+  hsync = 0;
   numHalflines = 262;
   numFields = 1;
   cyclesPerHalfline = 1000;
@@ -35,7 +41,6 @@ u32 VI::Read(u32 paddr) const {
     default:
       util::panic("Unimplemented VI[%08X] read\n", paddr);
   }
-  return 0;
 }
 
 void VI::Write(MI& mi, Registers& regs, u32 paddr, u32 val) {
diff --git a/src/n64/core/rsp/decode.cpp b/src/n64/core/rsp/decode.cpp
index 7cce97b2..4b8744ac 100644
--- a/src/n64/core/rsp/decode.cpp
+++ b/src/n64/core/rsp/decode.cpp
@@ -81,15 +81,15 @@ void RSP::Exec(MI &mi, Registers &regs, RDP &rdp, u32 instr) {
   u8 mask = (instr >> 26) & 0x3F;
   switch(mask) {
     //case 0x00: special(*this, instr); break;
-    //case 0x01: regimm(*this, instr); break;
-    //case 0x02: j(instr); break;
+    case 0x01: regimm(*this, instr); break;
+    case 0x02: j(instr); break;
     //case 0x03: jal(instr); break;
     //case 0x04: b(instr, gpr[RT(instr)] == gpr[RS(instr)]); break;
     //case 0x05: b(instr, gpr[RT(instr)] != gpr[RS(instr)]); break;
     //case 0x07: b(instr, gpr[RS(instr)] > 0); break;
-    //case 0x08: case 0x09: addi(instr); break;
+    case 0x08: case 0x09: addi(instr); break;
     //case 0x0C: andi(instr); break;
-    //case 0x0D: ori(instr); break;
+    case 0x0D: ori(instr); break;
     //case 0x0F: lui(instr); break;
     //case 0x10: cop0(mi, regs, *this, rdp, instr); break;
     //case 0x12: cop2(*this, instr); break;
@@ -100,7 +100,7 @@ void RSP::Exec(MI &mi, Registers &regs, RDP &rdp, u32 instr) {
     //case 0x2B: sw(instr); break;
     //case 0x32: lwc2(*this, instr); break;
     //case 0x3A: swc2(*this, instr); break;
-    default: util::panic("Unhandled RSP instruction {} {}\n", (mask >> 3) & 7, mask & 7);
+    default: util::panic("Unhandled RSP instruction ({:06b})\n", mask);
   }
 }
 }
\ No newline at end of file
diff --git a/src/n64/core/rsp/instructions.cpp b/src/n64/core/rsp/instructions.cpp
index c39a4e2d..ad6a9a4b 100644
--- a/src/n64/core/rsp/instructions.cpp
+++ b/src/n64/core/rsp/instructions.cpp
@@ -91,7 +91,10 @@ void RSP::add(u32 instr) {
 }
 
 void RSP::addi(u32 instr) {
-
+  s32 op1 = gpr[RS(instr)];
+  s16 op2 = instr;
+  s32 result = op1 + op2;
+  gpr[RT(instr)] = result;
 }
 
 void RSP::and_(u32 instr) {
@@ -128,7 +131,8 @@ void RSP::lqv(u32 instr) {
 }
 
 void RSP::j(u32 instr) {
-
+  u32 target = (instr & 0x3ffffff) << 2;
+  nextPC = target;
 }
 
 void RSP::jal(u32 instr) {
@@ -148,7 +152,8 @@ void RSP::or_(u32 instr) {
 }
 
 void RSP::ori(u32 instr) {
-
+  s16 imm = instr;
+  gpr[RT(instr)] = imm | gpr[RS(instr)];
 }
 
 void RSP::sb(u32 instr) {