diff --git a/include/PR/os_host.h b/include/PR/os_host.h
index 21e30ef..008292d 100644
--- a/include/PR/os_host.h
+++ b/include/PR/os_host.h
@@ -69,59 +69,13 @@ extern void __osInitialize_common(void);
 
 #else
 
-/* PARTNER-N64 */
-#if defined(PTN64)
-extern void __osInitialize_kmc(void);
-#define osReadHost  osReadHost_pt
-#define osWriteHost osWriteHost_pt
-#define osInitialize()                                                                                                 \
-    {                                                                                                                  \
-        __osInitialize_common();                                                                                       \
-        __osInitialize_kmc();                                                                                          \
-    }
-
-/* MONEGI SMART PACK A */
-#elif defined(MWN64)
-extern void __osInitialize_msp(void);
-#define osReadHost  osReadHost_pt
-#define osWriteHost osWriteHost_pt
-#define osInitialize()                                                                                                 \
-    {                                                                                                                  \
-        __osInitialize_common();                                                                                       \
-        __osInitialize_msp();                                                                                          \
-    }
-
-/* IS-Viewer(for Debugger) */
-#elif defined(ISV64)
-extern void __osInitialize_isv(void);
-#define osInitialize()                                                                                                 \
-    {                                                                                                                  \
-        __osInitialize_common();                                                                                       \
-        __osInitialize_isv();                                                                                          \
-    }
-
-/* Emulation board for INDY */
-#elif defined(EMU64)
-extern void __osInitialize_emu(void);
-#define osInitialize()                                                                                                 \
-    {                                                                                                                  \
-        __osInitialize_common();                                                                                       \
-        __osInitialize_emu();                                                                                          \
-    }
-
-#else
-/* Default (auto detect) */
 extern void __osInitialize_autodetect(void);
-extern void __osInitialize_msp(void);
-extern void __osInitialize_kmc(void);
 extern void __osInitialize_isv(void);
-extern void __osInitialize_emu(void);
 #define osInitialize()                                                                                                 \
     {                                                                                                                  \
         __osInitialize_common();                                                                                       \
         __osInitialize_autodetect();                                                                                   \
     }
-#endif
 
 #endif /* _FINAL_ROM */
 
diff --git a/include/assert.h b/include/assert.h
index f34a33b..4ecfc4c 100644
--- a/include/assert.h
+++ b/include/assert.h
@@ -6,7 +6,9 @@
 #define assert(EX) ((void)0)
 #else
 extern void __assert(const char*, const char*, int);
-#define assert(EX) ((EX) ? ((void)0) : __assert("EX", __FILE__, __LINE__))
+extern void __assertf(const char* exp, const char* filename, int line, const char* fmt, ...);
+#define assert(EX)            ((EX) ? ((void)0) : __assert(#EX, __FILE__, __LINE__))
+#define assertf(EX, fmt, ...) ((EX) ? ((void)0) : __assertf(#EX, __FILE__, __LINE__, fmt, ##__VA_ARGS__))
 #endif /* NDEBUG */
 
 #endif /* !__ASSERT_H__ */
diff --git a/src/debug/assert.c b/src/debug/assert.c
index ffdb5ee..8763f17 100644
--- a/src/debug/assert.c
+++ b/src/debug/assert.c
@@ -1,12 +1,28 @@
 #include "os.h"
 #include "PRinternal/osint.h"
 #include "osint_debug.h"
+#include <stdarg.h>
 
 void __assertBreak(void);
 
 void __assert(const char* exp, const char* filename, int line) {
 #ifndef _FINALROM
     osSyncPrintf("\nASSERTION FAULT: %s, %d: \"%s\"\n", filename, line, exp);
-    __assertBreak; // Doesn't actually do anything, but is needed for matching
+    __assertBreak();
+#endif
+}
+
+void __assertf(const char* exp, const char* filename, int line, const char* fmt, ...) {
+#ifndef _FINALROM
+    va_list args;
+
+    va_start(args, fmt);
+
+    osSyncPrintf("\nASSERTION FAULT: %s, %d: \"%s\"\n", filename, line, exp);
+    osSyncPrintf(fmt, args);
+    osSyncPrintf("\n");
+
+    va_end(args);
+    __assertBreak(); // Doesn't actually do anything, but is needed for matching
 #endif
 }
diff --git a/src/os/initialize.c b/src/os/initialize.c
index 2748b4a..fedb2fd 100644
--- a/src/os/initialize.c
+++ b/src/os/initialize.c
@@ -96,14 +96,6 @@ void INITIALIZE_FUNC() {
 
 void __osInitialize_autodetect(void) {
 #ifndef _FINALROM
-    if (__checkHardware_msp()) {
-        __osInitialize_msp();
-    } else if (__checkHardware_kmc()) {
-        __osInitialize_kmc();
-    } else if (__checkHardware_isv()) {
-        __osInitialize_isv();
-    } else {
-        __osInitialize_emu();
-    }
+    __osInitialize_isv();
 #endif
 }
diff --git a/src/os/initialize_emu.c b/src/os/initialize_emu.c
deleted file mode 100644
index 1f0e5f3..0000000
--- a/src/os/initialize_emu.c
+++ /dev/null
@@ -1,28 +0,0 @@
-#ifndef _FINALROM
-
-#include "stdlib.h"
-#include "PR/os_internal.h"
-#include "PR/rdb.h"
-#include "PRinternal/osint.h"
-
-typedef struct {
-    /* 0x0 */ unsigned int inst1;
-    /* 0x4 */ unsigned int inst2;
-    /* 0x8 */ unsigned int inst3;
-    /* 0xC */ unsigned int inst4;
-} __osExceptionVector;
-
-static void* proutSyncPrintf(void* str, const char* buf, size_t n) {
-    size_t sent = 0;
-
-    while (sent < n) {
-        sent += __osRdbSend(buf + sent, n - sent, RDB_TYPE_GtoH_PRINT);
-    }
-    return 1;
-}
-
-void __osInitialize_emu(void) {
-    __printfunc = proutSyncPrintf;
-}
-
-#endif
diff --git a/src/os/initialize_isv.c b/src/os/initialize_isv.c
index d8d85d2..e5cd78f 100644
--- a/src/os/initialize_isv.c
+++ b/src/os/initialize_isv.c
@@ -25,12 +25,12 @@ void MonitorInitBreak(void);
 
 #define ISV_BUFFER_LEN (0x10000 - 0x20)
 
-#define IS64_MAGIC 'IS64'
+#define IS64_MAGIC 0x49533634 // 'IS64'
 
 __osExceptionVector ramOldVector ALIGNED(0x8);
 u32 gISVFlag;
 u16 gISVChk;
-u32 gISVDbgPrnAdrs;
+u32 gISVDbgPrnAdrs = 0x13FF0000;
 u32 leoComuBuffAdd;
 
 static OSPiHandle* is_Handle;
@@ -97,78 +97,31 @@ static void* is_proutSyncPrintf(void* arg, const u8* str, u32 count) {
     return 1;
 }
 
-int __checkHardware_isv(void) {
-    u32 i = 0;
-    u32 data;
-    u32 save[4];
-    OSPiHandle* hnd = osCartRomInit();
-
-    gISVDbgPrnAdrs = 0;
-    leoComuBuffAdd = 0;
-    gISVFlag = IS64_MAGIC;
-    gISVChk = 0;
-
-    for (i = 0; i < 4; i++) {
-        osEPiReadIo(hnd, 0xB0000100 + i * 4, &save[i]);
-    }
-
-#ifndef __GNU__ // BUG: data is used uninitialized for GCC
-    data = 0;
-#endif
-    osEPiWriteIo(hnd, 0xB000010C, data);
-    data = IS64_MAGIC;
-    osEPiWriteIo(hnd, 0xB0000100, IS64_MAGIC);
-
-    for (i = 0; i < 0x20000; i++) {
-        osEPiReadIo(hnd, 0xB000010C, &data);
-        if (data == IS64_MAGIC) {
-            data = 0;
-            osEPiWriteIo(hnd, 0xB0000100, data);
-            gISVChk |= 1;
-            osEPiReadIo(hnd, 0xB0000104, &gISVDbgPrnAdrs);
-            osEPiReadIo(hnd, 0xB0000108, &leoComuBuffAdd);
-            break;
-        }
-    }
-
-    for (i = 0; i < 4; i++) {
-        osEPiWriteIo(hnd, 0xB0000100 + i * 4, save[i]);
-    }
-
-    osEPiReadIo(hnd, 0xBFF00000, &data);
-
-    gISVChk |= ((data == IS64_MAGIC) ? 2 : 0);
-
-    return (gISVChk != 0) ? TRUE : FALSE;
-}
-
 void __osInitialize_isv(void) {
     void (*fn)(void);
     OSPiHandle* hnd;
     s32 pad;
     s32 pad2;
 
-    if (gISVFlag == IS64_MAGIC || __checkHardware_isv()) {
-        if (gISVDbgPrnAdrs != 0) {
-            __printfunc = is_proutSyncPrintf;
-            isPrintfInit();
-        }
-        if (gISVChk & 2) {
-            hnd = osCartRomInit();
+    if (gISVDbgPrnAdrs != 0) {
+        __printfunc = is_proutSyncPrintf;
+        isPrintfInit();
+    }
+    if (gISVChk & 2) {
+        hnd = osCartRomInit();
 
-            ramOldVector = *(__osExceptionVector*)E_VEC;
-            *(__osExceptionVector*)E_VEC = __isExpJP;
+        ramOldVector = *(__osExceptionVector*)E_VEC;
+        *(__osExceptionVector*)E_VEC = __isExpJP;
 
-            osWritebackDCache(&ramOldVector, 0x10);
-            osInvalICache(&ramOldVector, 0x10);
-            osWritebackDCache(0x80000000, 0x190);
-            osInvalICache(0x80000000, 0x190);
-            osEPiReadIo(hnd, 0xBFF00010, (u32*)&fn);
-            fn();
-        }
-        if (gISVChk & 2) {
-            MonitorInitBreak();
-        }
+        osWritebackDCache(&ramOldVector, 0x10);
+        osInvalICache(&ramOldVector, 0x10);
+        osWritebackDCache(0x80000000, 0x190);
+        osInvalICache(0x80000000, 0x190);
+        osEPiReadIo(hnd, 0xBFF00010, (u32*)&fn);
+        fn();
+    }
+    if (gISVChk & 2) {
+        MonitorInitBreak();
     }
 }
 
diff --git a/src/os/initialize_kmc.c b/src/os/initialize_kmc.c
deleted file mode 100644
index 4328da9..0000000
--- a/src/os/initialize_kmc.c
+++ /dev/null
@@ -1,152 +0,0 @@
-#ifndef _FINALROM
-
-#include "PR/os_internal.h"
-#include "PR/rcp.h"
-#include "PRinternal/osint.h"
-
-typedef struct {
-    /* 0x0 */ unsigned int inst1;
-    /* 0x4 */ unsigned int inst2;
-    /* 0x8 */ unsigned int inst3;
-    /* 0xC */ unsigned int inst4;
-} __osExceptionVector;
-
-extern __osExceptionVector __ptExceptionPreamble[];
-
-static volatile unsigned int* stat = (unsigned*)0xbff08004;
-static volatile unsigned int* wport = (unsigned*)0xbff08000;
-static volatile unsigned int* piok = (unsigned*)PHYS_TO_K1(PI_STATUS_REG);
-
-static void rmonPutchar(char c) {
-    u32 data;
-
-    while (TRUE) {
-        osPiReadIo(stat, &data);
-        if (data & 4) {
-            osPiWriteIo(wport, c);
-            break;
-        }
-    }
-}
-
-static void* kmc_proutSyncPrintf(void* str, const char* buf, int n) {
-    int i;
-    char c;
-    char* p;
-    char* q;
-    char xbuf[128];
-    static int column = 0;
-
-    p = &xbuf;
-
-    for (i = 0; i < n; i++) {
-        c = *buf++;
-
-        switch (c) {
-            case '\n':
-                *p++ = '\n';
-                column = 0;
-                break;
-            case '\t':
-                do {
-                    *p++ = ' ';
-                } while (++column % 8);
-                break;
-            default:
-                column++;
-                *p++ = c;
-                break;
-        }
-
-        if (c == '\n' || (p - xbuf) > 100) {
-            rmonPutchar((p - xbuf) - 1);
-
-            q = xbuf;
-            while (q != p) {
-                rmonPutchar(*q++);
-            }
-            p = xbuf;
-        }
-    }
-    if (p != xbuf) {
-        rmonPutchar((p - xbuf) - 1);
-
-        q = xbuf;
-        while (q != p) {
-            rmonPutchar(*q++);
-        }
-    }
-    return (void*)1;
-}
-
-extern u32 __kmc_pt_mode;
-
-void __osInitialize_kmc(void) {
-    if (!__kmc_pt_mode) {
-        int (*fnc)();
-        unsigned int* src;
-        unsigned int* dst;
-        unsigned int monadr;
-        volatile unsigned int* mon;
-        volatile unsigned int* stat;
-
-        stat = (unsigned*)0xbff08004;
-        mon = (unsigned*)0xBFF00000;
-        if (*mon != 0x4B4D4300) {
-            return;
-        }
-
-        src = (unsigned*)__ptExceptionPreamble;
-        dst = (unsigned*)E_VEC;
-        *dst++ = *src++;
-        *dst++ = *src++;
-        *dst++ = *src++;
-        src += 2;
-        dst += 2;
-        *dst++ = *src++;
-        *dst++ = *src++;
-        *dst++ = *src++;
-
-        osWritebackDCache(E_VEC, 0x24);
-        osInvalICache(E_VEC, 0x24);
-
-        __kmc_pt_mode = TRUE;
-
-        if ((*stat & 0x10) == 0) {
-            monadr = *(mon + 1);
-            if (monadr != 0xBFF00000) {
-                unsigned int* src;
-                unsigned int* dst = monadr | 0x20000000;
-                unsigned int ct = 0x2000 / 4;
-
-                src = 0xBFF00000;
-
-                while (ct != 0) {
-                    *dst++ = *src++;
-                    ct--;
-                }
-            }
-            fnc = monadr + 8;
-            fnc(0x4B4D4300, 0);
-        }
-        __printfunc = kmc_proutSyncPrintf;
-    }
-}
-
-int __checkHardware_kmc(void) {
-    volatile unsigned int* mon = (unsigned*)0xBFF00000;
-
-    if (*mon == 0x4B4D4300) {
-        mon = (unsigned*)0xBFF00010;
-
-        if (*mon == 0xB0FFB000) {
-            return TRUE;
-        } else {
-            return FALSE;
-        }
-    } else {
-        return FALSE;
-    }
-}
-
-#endif
diff --git a/src/os/initialize_msp.c b/src/os/initialize_msp.c
deleted file mode 100644
index c86d7e8..0000000
--- a/src/os/initialize_msp.c
+++ /dev/null
@@ -1,152 +0,0 @@
-#ifndef _FINALROM
-
-#include "PR/os_internal.h"
-#include "PR/rcp.h"
-#include "PRinternal/osint.h"
-
-typedef struct {
-    /* 0x0 */ unsigned int inst1;
-    /* 0x4 */ unsigned int inst2;
-    /* 0x8 */ unsigned int inst3;
-    /* 0xC */ unsigned int inst4;
-} __osExceptionVector;
-
-extern __osExceptionVector __ptExceptionPreamble[];
-
-static volatile unsigned int* stat = (unsigned*)0xbff08004;
-static volatile unsigned int* wport = (unsigned*)0xbff08000;
-static volatile unsigned int* piok = (unsigned*)PHYS_TO_K1(PI_STATUS_REG);
-
-static void rmonPutchar(char c) {
-    u32 data;
-
-    while (TRUE) {
-        osPiReadIo(stat, &data);
-        if (data & 4) {
-            osPiWriteIo(wport, c);
-            break;
-        }
-    }
-}
-
-static void* msp_proutSyncPrintf(void* str, const char* buf, int n) {
-    int i;
-    char c;
-    char* p;
-    char* q;
-    char xbuf[128];
-    static int column = 0;
-
-    p = &xbuf;
-
-    for (i = 0; i < n; i++) {
-        c = *buf++;
-
-        switch (c) {
-            case '\n':
-                *p++ = '\n';
-                column = 0;
-                break;
-            case '\t':
-                do {
-                    *p++ = ' ';
-                } while (++column % 8);
-                break;
-            default:
-                column++;
-                *p++ = c;
-                break;
-        }
-
-        if (c == '\n' || (p - xbuf) > 100) {
-            rmonPutchar((p - xbuf) - 1);
-
-            q = xbuf;
-            while (q != p) {
-                rmonPutchar(*q++);
-            }
-            p = xbuf;
-        }
-    }
-    if (p != xbuf) {
-        rmonPutchar((p - xbuf) - 1);
-
-        q = xbuf;
-        while (q != p) {
-            rmonPutchar(*q++);
-        }
-    }
-    return (void*)1;
-}
-
-extern u32 __kmc_pt_mode;
-
-void __osInitialize_msp(void) {
-    if (!__kmc_pt_mode) {
-        int (*fnc)();
-        unsigned int* src;
-        unsigned int* dst;
-        unsigned int monadr;
-        volatile unsigned int* mon;
-        volatile unsigned int* stat;
-
-        stat = (unsigned*)0xbff08004;
-        mon = (unsigned*)0xBFF00000;
-        if (*mon != 0x4B4D4300) {
-            return;
-        }
-
-        src = (unsigned*)__ptExceptionPreamble;
-        dst = (unsigned*)E_VEC;
-        *dst++ = *src++;
-        *dst++ = *src++;
-        *dst++ = *src++;
-        src += 2;
-        dst += 2;
-        *dst++ = *src++;
-        *dst++ = *src++;
-        *dst++ = *src++;
-
-        osWritebackDCache(E_VEC, 0x24);
-        osInvalICache(E_VEC, 0x24);
-
-        __kmc_pt_mode = TRUE;
-
-        if ((*stat & 0x10) == 0) {
-            monadr = *(mon + 1);
-            if (monadr != 0xBFF00000) {
-                unsigned int* src;
-                unsigned int* dst = monadr | 0x20000000;
-                unsigned int ct = 0x2000 / 4;
-
-                src = 0xBFF00000;
-
-                while (ct != 0) {
-                    *dst++ = *src++;
-                    ct--;
-                }
-            }
-            fnc = monadr + 8;
-            fnc(0x4B4D4300, 0);
-        }
-        __printfunc = msp_proutSyncPrintf;
-    }
-}
-
-int __checkHardware_msp(void) {
-    volatile unsigned int* mon = (unsigned*)0xBFF00000;
-
-    if (*mon == 0x4B4D4300) {
-        mon = (unsigned*)0xBFF00010;
-
-        if (*mon == 0) {
-            return TRUE;
-        } else {
-            return FALSE;
-        }
-    } else {
-        return FALSE;
-    }
-}
-
-#endif