diff --git a/debug/boot.txt b/debug/boot.txt
index 976530d..c3b9e2a 100644
--- a/debug/boot.txt
+++ b/debug/boot.txt
@@ -1,7 +1,10 @@
 target remote localhost:1234
 set disassembly-flavor att
-symbol-file ./system/realmode/setup.sym
+add-symbol-file ./system/realmode/setup.sym 0x902f6
 set architecture i8086
 break *0x90200
 cont
 clear *0x90200
+break main
+cont
+clear main
diff --git a/debug/gdbinit b/debug/gdbinit
index 83ad9d2..822e958 100644
--- a/debug/gdbinit
+++ b/debug/gdbinit
@@ -882,7 +882,12 @@ class Source(Dashboard.Module):
         if not gdb.selected_thread().is_stopped():
             return []
         # try to fetch the current line (skip if no line information)
-        sal = gdb.selected_frame().find_sal()
+        arch = gdb.parameter('architecture');
+        if arch=="i8086":
+             realpc=int(gdb.parse_and_eval('$pc'))+int(gdb.parse_and_eval('$cs'))*16
+             sal = gdb.find_pc_line(realpc)
+        else:
+             sal = gdb.selected_frame().find_sal()
         current_line = sal.line
         if current_line == 0:
             return []
@@ -962,7 +967,12 @@ instructions constituting the current statement are marked, if available."""
         if not gdb.selected_thread().is_stopped():
             return []
         line_info = None
+        arch = gdb.parameter('architecture');
         frame = gdb.selected_frame()  # PC is here
+        if arch=="i8086":
+              realpc=frame.pc()+int(gdb.parse_and_eval('$cs'))*16
+        else:
+              realpc=frame.pc()
         disassemble = frame.architecture().disassemble
         try:
             # try to fetch the function boundaries using the disassemble command
@@ -971,21 +981,20 @@ instructions constituting the current statement are marked, if available."""
             end = int(re.split('[ :]', output[-3][3:], 1)[0], 16)
             asm = disassemble(start, end_pc=end)
             # find the location of the PC
-            pc_index = next(index for index, instr in enumerate(asm)
-                            if instr['addr'] == frame.pc())
+            pc_index = next(index for index, instr in enumerate(asm) if instr['addr'] == realpc)
             start = max(pc_index - self.context, 0)
             end = pc_index + self.context + 1
             asm = asm[start:end]
             # if there are line information then use it, it may be that
             # line_info is not None but line_info.last is None
-            line_info = gdb.find_pc_line(frame.pc())
+            line_info = gdb.find_pc_line(realpc)
             line_info = line_info if line_info.last else None
         except (gdb.error, StopIteration):
             # if it is not possible (stripped binary or the PC is not present in
             # the output of `disassemble` as per issue #31) start from PC and
             # end after twice the context
             try:
-                asm = disassemble(frame.pc(), count=2 * self.context + 1)
+                asm = disassemble(realpc, count=2 * self.context + 1)
             except gdb.error as e:
                 msg = '{}'.format(e)
                 return [ansi(msg, R.style_error)]
@@ -1046,7 +1055,7 @@ instructions constituting the current statement are marked, if available."""
             format_string = '{}{}{}{}{}'
             indicator = ' '
             text = ' ' + highlighter.process(text)
-            if addr == frame.pc():
+            if addr == realpc:
                 if not R.ansi:
                     indicator = '>'
                 addr_str = ansi(addr_str, R.style_selected_1)
diff --git a/include/setup.h b/include/setup.h
index b51e6cf..0ca2297 100644
--- a/include/setup.h
+++ b/include/setup.h
@@ -91,12 +91,10 @@ u8 testA20(void);
 void enableA20kbc(void);
 void enableA20fast(void);
 u8 enableA20(void);
-void memset(void *dst, u8 val, u32 count, u32 size);
-void memcpy(void *src, void *dst, u32 count, u32 size);
-void initselectors(u32 executingoffset);
+void memcpyto(void *src, void *dst, u32 count);
 void makegdtdes(u32 base, u32 limite, u8 acces, u8 flags, gdtdes * desc);
 void initgdt();
 void maskinterrupts(void);
 void initcoprocessor(void);
-void initpmode(u32 offset);
+void initpmode();
 void main(void);
diff --git a/include/system.h b/include/system.h
index 3c16033..9a6e597 100644
--- a/include/system.h
+++ b/include/system.h
@@ -1,4 +1,5 @@
 /*******************************************************************************/
 /* COS2000 - Compatible Operating System - LGPL v3 - Hordé Nicolas             */
 /*                                                                             */
-extern  restart;
+extern restart;
+int main(u8* info);
diff --git a/lib/gdt.c b/lib/gdt.c
index 899e7f3..f299569 100644
--- a/lib/gdt.c
+++ b/lib/gdt.c
@@ -6,9 +6,61 @@
 #include "types.h"
 #include "memory.h"
 
+ /* registre gdt */
+static struct gdtr gdtreg;
+
+/* table de GDT */
+static gdtdes gdt[GDT_SIZE];
+
 /* TSS */
 static struct tss tss0;
 
+/*******************************************************************************/
+/* Créé un descripteur GDT */
+
+void makegdtdes(u32 base, u32 limite, u8 acces, u8 flags, gdtdes * desc)
+{
+	desc->lim0_15 = (limite & 0xffff);
+	desc->base0_15 = (base & 0xffff);
+	desc->base16_23 = (base & 0xff0000) >> 16;
+	desc->acces = acces;
+	desc->lim16_19 = (limite & 0xf0000) >> 16;
+	desc->flags = (flags & 0xf);
+	desc->base24_31 = (base & 0xff000000) >> 24;
+	return;
+}
+
+/*******************************************************************************/
+/* Initialise la GDT */
+
+void initgdt(u32 offset)
+{
+	makegdtdes(0x0, 0x00000, 0x00, 0x00, &gdt[0]);	/* descripteur nul         */
+	makegdtdes(0x0, 0xFFFFF, SEG_PRESENT | SEG_NORMAL | SEG_CODE | SEG_RING0 | SEG_READ | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[1]);	/* code -> SEL_KERNEL_CODE */
+	makegdtdes(0x0, 0x00000, SEG_PRESENT | SEG_NORMAL | SEG_DATA | SEG_RING0 | SEG_EXPAND_DOWN | SEG_READ_WRITE | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[2]);	/* pile -> SEL_KERNEL_STACK */
+	makegdtdes(0x0, 0xFFFFF, SEG_PRESENT | SEG_NORMAL | SEG_CODE | SEG_RING3 | SEG_CONFORMING | SEG_READ | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[3]);	/* code -> SEL_USER_CODE */
+	makegdtdes(0x0, 0x00000, SEG_PRESENT | SEG_NORMAL | SEG_DATA | SEG_RING3 | SEG_EXPAND_DOWN | SEG_READ_WRITE | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[4]);	/* pile -> SEL_USER_STACK */
+	makegdtdes(0x0, 0xFFFFF, SEG_PRESENT | SEG_NORMAL | SEG_DATA | SEG_RING0 | SEG_READ_WRITE | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[5]);	/* data -> SEL_KERNEL_DATA */
+	makegdtdes(0x0, 0xFFFFF, SEG_PRESENT | SEG_NORMAL | SEG_DATA | SEG_RING3 | SEG_READ_WRITE | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[6]);	/* data -> SEL_USER_DATA */
+
+	tss0.trapflag = 0x00;
+	tss0.iomap = 0x00;
+	tss0.esp0 = 0x6000;
+	tss0.ss0 = SEL_TSS;
+
+	makegdtdes(&tss0, 0x67, SEG_PRESENT | SEG_CODE | SEG_RING3 | SEG_ACCESSED, 0x00, &gdt[7]);	/* descripteur de tss */
+
+	/* initialise le registre gdt */
+	gdtreg.limite = GDT_SIZE * sizeof(gdtdes);
+	gdtreg.base = GDT_ADDR;
+	/* recopie de la GDT a son adresse */
+	memcpy(&gdt, (u8 *) gdtreg.base, gdtreg.limite, 1);
+	/* chargement du registre GDT */
+	lgdt(gdtreg);
+	/* initialisation des segments */
+	initselectors(offset);
+}
+
 /*******************************************************************************/
 /* Initialise les selecteurs avec la GDT */
 
diff --git a/makefile b/makefile
index bb87f50..8c670db 100755
--- a/makefile
+++ b/makefile
@@ -1,4 +1,4 @@
-DEBUG=exec gnome-terminal --geometry=120x40+1+1 -x ./debug/debug.sh
+DEBUG=exec gnome-terminal --geometry=120x55+1+1 -x ./debug/debug.sh
 REMOVE=rm -f
 INSTALL=sudo apt-get install
 COPY=cp
@@ -81,15 +81,15 @@ backup: clean
 	cd .. 
 	tar cf - Source\ C | gzip -f - > backup.tar.gz
 
-test: programs bits32 harddisk qemu
+test: tools programs bits32 harddisk qemu
 
-test64: programs bits64 uefi qemu64
+test64: tools programs bits64 uefi qemu64
 
 retest: littleclean test
 
 retest64: littleclean test64
 
-testbochs: programs bits32 harddisk bochs-debug
+testbochs: tools programs bits32 harddisk bochs-debug
 
 view:
 	hexdump  -C ./final/harddisk.img.final|head -c10000
@@ -104,15 +104,15 @@ redebug64: littleclean debug-system64
 
 kernel: debug-kernel
 
-debug-boot: programs bits32 harddisk qemu-debug
+debug-boot: tools programs bits32 harddisk qemu-debug
 	sleep 2
 	$(DEBUG) ./debug/boot.txt
 
-debug-system: programs bits32 harddisk qemu-debug
+debug-system: tools programs bits32 harddisk qemu-debug
 	sleep 2
 	$(DEBUG) ./debug/system.txt
 
-debug-system64: programs bits64 uefi qemu-debug64
+debug-system64: tools programs bits64 uefi qemu-debug64
 	sleep 2
 	$(DEBUG) ./debug/system.txt
 
diff --git a/system/makefile b/system/makefile
index ad77049..3121d83 100755
--- a/system/makefile
+++ b/system/makefile
@@ -34,7 +34,7 @@ togit: clean indent
 piggy.o: piggy.S
 	$(ASM) $@ $^ 
 
-system: systemc.o system.o ../lib/libs.o
+system: system.o system_asm.o ../lib/libs.o
 	$(LINK) -T system.ld system.o ../lib/libs.o
 	$(OBJDEBUG) system system.sym
 	$(NM) system > system.map
@@ -51,10 +51,10 @@ piggy.S: system.bin.gz
 realmode/setup.bin:
 	make -C realmode
 
-systemc.o: system.c
+system.o: system.c
 	$(GCC) $@ $^
 
-system.o: system.S
+system_asm.o: system_asm.S
 	$(ASM) $@ $^
 
 clean:
diff --git a/system/realmode/makefile b/system/realmode/makefile
index 0ff652c..88f9fbf 100644
--- a/system/realmode/makefile
+++ b/system/realmode/makefile
@@ -1,4 +1,4 @@
-GCC=gcc -O0 -g -nostdinc -ffreestanding -Wall -Wstrict-prototypes -fno-stack-protector -march=i386 -m16 -mpreferred-stack-boundary=2 -mregparm=3 -fno-pic -fno-strict-aliasing -mno-mmx -mno-sse -w -I ../../include -c
+GCC=gcc -O0 -g -nostdinc -ffreestanding -Wall -Wstrict-prototypes -fno-stack-protector -march=i386 -m16 -fno-pic -fno-strict-aliasing -mno-mmx -mno-sse -w -I ../../include -c
 ASM=gcc -O0 -m16 -march=i386 -fno-pic -D__ASSEMBLY__ -I ../ -I ../../include -c -o
 LINK=ld -m elf_i386 -n
 CONVERT=dos2unix
@@ -13,8 +13,8 @@ $(eval VERSION=$(shell git describe --tags))
 all: setup.bin 
 	sync
 
-setup: setupc.o setup.o 
-	$(LINK) -T setup.ld setupc.o setup.o
+setup: setupc.o setup.o setup32.o
+	$(LINK) -T setup.ld setupc.o setup.o setup32.o
 
 setup.bin: setup
 	$(OBJCOPY) $^ $@	
@@ -27,6 +27,9 @@ setupc.o: setup.c
 setup.o: setup.S
 	$(ASM) $@ $^
 
+setup32.o: pmode.S
+	$(ASM) $@ $^
+
 clean:
 	$(REMOVE) setup
 	$(REMOVE) *.o
diff --git a/system/realmode/pmode.S b/system/realmode/pmode.S
new file mode 100644
index 0000000..8c0cbe3
--- /dev/null
+++ b/system/realmode/pmode.S
@@ -0,0 +1,40 @@
+#include "memory.h"
+#include "gdt.h"
+.text
+.code16
+
+.global gotopmode
+gotopmode:
+	jmp	1f
+1:
+	xorl  %eax,%eax
+	movl  %ds,%ax
+	shl   $0x4,%eax
+	add   %eax,(2f)
+	movl	%cr0, %eax
+	orb	$0x01, %al
+	movl	%eax, %cr0
+	.byte	0x66, 0xea
+2:	.long	pmode
+	.word	SEL_KERNEL_CODE
+
+.code32
+.section ".text32","ax"
+.global pmode
+pmode:
+	movw $SEL_KERNEL_DATA, %ax
+      movw %ax, %ds
+      movw %ax, %es
+      movw %ax, %fs
+      movw %ax, %gs
+      movl $KERNEL_CODE_ADDR, %ebx
+      movw $SEL_KERNEL_STACK, %ax
+      movw %ax, %ss
+      movl $KERNEL_STACK_ADDR, %esp
+	xor %eax,%eax
+	xor %ecx,%ecx
+	xor %edx,%edx
+	xor %esi,%esi
+	xor %edi,%edi
+	xor %ebp,%ebp
+	jmp *%ebx
diff --git a/system/realmode/setup.S b/system/realmode/setup.S
index 7fb5b42..98a00bb 100644
--- a/system/realmode/setup.S
+++ b/system/realmode/setup.S
@@ -123,7 +123,7 @@ setup_move_size: .word  0x8000		# size to move, when setup is not
 
 code32_start:				# here loaders can put a different
 					# start address for 32-bit code.
-		.long	0x100000	# 0x100000 = default for big kernel
+		.long	LOAD_PHYSICAL_ADDR	# 0x100000 = default for big kernel
 
 ramdisk_image:	.long	0		# address of loaded ramdisk image
 					# Here the loader puts the 32-bit
diff --git a/system/realmode/setup.c b/system/realmode/setup.c
index 759e70f..3b55d84 100644
--- a/system/realmode/setup.c
+++ b/system/realmode/setup.c
@@ -175,86 +175,37 @@ u8 enableA20(void)
        int loops = LOOPS_A20_ENABLE;
        int kbcerr;
        while (loops--) {
-	       if (testA20())
-		       return 1;
+	       if (!testA20())
+		       return NULL;
 	       kbcerr = empty8042();
-	       if (testA20())
-		       return 1;
+	       if (!testA20())
+		       return NULL;
 	       if (!kbcerr) {
 		       enableA20kbc();
-		       if (testA20())
-			       return 1;
+		       if (!testA20())
+			       return NULL;
 	       }
 	       enableA20fast();
-	       if (testA20())
+	       if (!testA20())
 		       return NULL;
        }
        return 1;
 }
 
-/*******************************************************************************/
-/* Copie un octet une ou plusieurs fois en mémoire */
-
-void memset(void *dst, u8 val, u32 count, u32 size)
-{
-	u8     *d = (u8 *) dst;
-	if (size > 0)
-		size--;
-	for (; count != 0; count--)
-	{
-		*(d++) = val;
-		d += size;
-	}
-}
-
 /*******************************************************************************/
 /* Copie une portion de mémoire vers une autre */
 
-void memcpy(void *src, void *dst, u32 count, u32 size)
+void memcpyto(void *src, void *dst, u32 count)
 {
-	u8     *s = (u8 *) src;
-	u8     *d = (u8 *) dst;
-	if (size > 0)
-		size--;
-	for (; count != 0; count--)
-	{
-		*(d++) = *(s++);
-		d += size;
-	}
+	asm("push %%es\n\
+           cld\n\
+           xor %%eax,%%eax\n\
+           mov %%ax,%%es\n\
+           rep movsb\n\
+           pop %%es"::"S" (src), "D" (dst), "c" (count):);
 }
 
 
-/*******************************************************************************/
-/* Initialise les selecteurs avec la GDT */
-
-void initselectors(u32 executingoffset)
-{
-	asm(" movl	%%cr0, %%eax \n \
-		orb	$0x00000001, %%eax \n \
-		movl	%%eax, %%cr0 \n \
-            ljmp %[code], $raz\n\
-		raz:\n \
-	.code32\n\
-		movw %[data], %%ax	\n \
-            movw %%ax, %%ds	\n \
-            movw %%ax, %%es	\n \
-            movw %%ax, %%fs	\n \
-            movw %%ax, %%gs   \n \
-            movl %[offset], %%ebx \n \
-            movw %[stack], %%ax \n \
-            movw %%ax, %%ss \n \
-            movl %[stackoff], %%esp \n \
-		xor %%eax,%%eax\n\
-		xor %%ebx,%%ebx\n\
-		xor %%ecx,%%ecx\n\
-		xor %%edx,%%edx\n\
-		xor %%esi,%%esi\n\
-		xor %%edi,%%edi\n\
-		xor %%ebp,%%ebp\n\
-		jmp %%ebx\n\
-	.code16gcc"::[data] "i"(SEL_KERNEL_DATA),[code] "i"(SEL_KERNEL_CODE),[stack] "i"(SEL_KERNEL_STACK),[stackoff] "i"(KERNEL_STACK_ADDR),[offset] "m"(executingoffset));
-}
-
 /*******************************************************************************/
 /* Créé un descripteur GDT */
 
@@ -278,16 +229,16 @@ void initgdt()
 	makegdtdes(0x0, 0x00000, 0x00, 0x00, &gdt[0]);	/* descripteur nul         */
 	makegdtdes(0x0, 0xFFFFF, SEG_PRESENT | SEG_NORMAL | SEG_CODE | SEG_RING0 | SEG_READ | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[1]);	/* code -> SEL_KERNEL_CODE */
 	makegdtdes(0x0, 0x00000, SEG_PRESENT | SEG_NORMAL | SEG_DATA | SEG_RING0 | SEG_EXPAND_DOWN | SEG_READ_WRITE | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[2]);	/* pile -> SEL_KERNEL_STACK */
-	makegdtdes(0x0, 0xFFFFF, SEG_PRESENT | SEG_NORMAL | SEG_CODE | SEG_RING3 | SEG_CONFORMING | SEG_READ | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[3]);	/* code -> SEL_USER_CODE */
-	makegdtdes(0x0, 0x00000, SEG_PRESENT | SEG_NORMAL | SEG_DATA | SEG_RING3 | SEG_EXPAND_DOWN | SEG_READ_WRITE | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[4]);	/* pile -> SEL_USER_STACK */
+	makegdtdes(0x0, 0x00000, 0x00, 0x00, &gdt[3]);	/* LIBRE */
+	makegdtdes(0x0, 0x00000, 0x00, 0x00, &gdt[4]);	/* LIBRE */
 	makegdtdes(0x0, 0xFFFFF, SEG_PRESENT | SEG_NORMAL | SEG_DATA | SEG_RING0 | SEG_READ_WRITE | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[5]);	/* data -> SEL_KERNEL_DATA */
-	makegdtdes(0x0, 0xFFFFF, SEG_PRESENT | SEG_NORMAL | SEG_DATA | SEG_RING3 | SEG_READ_WRITE | SEG_ACCESSED, GRANULARITY_4K | OPSIZE_32B | SYS_AVAILABLE, &gdt[6]);	/* data -> SEL_USER_DATA */
-	makegdtdes(0x0, 0x67, SEG_PRESENT | SEG_CODE | SEG_RING3 | SEG_ACCESSED, 0x00, &gdt[7]);	/* descripteur de tss */
+	makegdtdes(0x0, 0x00000, 0x00, 0x00, &gdt[6]);	/* LIBRE */
+	makegdtdes(0x0, 0x00000, 0x00, 0x00, &gdt[7]);	/* LIBRE */
 	/* initialise le registre gdt */
 	gdtreg.limite = GDT_SIZE * sizeof(gdtdes);
 	gdtreg.base = GDT_ADDR;
 	/* recopie de la GDT a son adresse */
-	memcpy(&gdt, (u8 *) gdtreg.base, gdtreg.limite, 1);
+	memcpyto(&gdt, (u8 *) gdtreg.base, gdtreg.limite);
 	/* chargement du registre GDT */
 	lgdt(gdtreg);
 }
@@ -311,7 +262,7 @@ void initcoprocessor(void)
 	iodelay();
 }
 
-void initpmode(u32 offset)
+void initpmode()
 {
 	if (enableA20()) {
 		showstr("impossible d'ouvrir la ligne A20...\n");
@@ -319,7 +270,7 @@ void initpmode(u32 offset)
 	}
 	maskinterrupts();
 	initgdt();
-	initselectors(offset);
+	gotopmode();		
 }
 
 void main(void)
@@ -334,5 +285,5 @@ void main(void)
 	showstr(" -Initialisation du coprocesseur\r\n");
 	initcoprocessor();
 	showstr(" -Passage en mode protege\r\n");
-	initpmode(0x10000);
+	initpmode();
 }
diff --git a/system/system.c b/system/system.c
index 22f59a1..ccc19e2 100644
--- a/system/system.c
+++ b/system/system.c
@@ -15,6 +15,7 @@
 #include "shell.h"
 #include "syscall.h"
 #include "memory.h"
+#include "system.h"
 
 static u8 warnmsg[] =
 	"\033[150C\033[8D\033[37m\033[1m[ \033[36mNON\033[37m  ]\033[0m";
@@ -59,6 +60,8 @@ int main(u8* info)
 	logo();
 
 	print("\033[37m\033[0m -Initilisation de la memoire virtuelle");
+	initgdt(&&next);
+next:
 	initpaging();
 	remap_memory(VESA_FBMEM);
 	ok();
diff --git a/system/system.S b/system/system_asm.S
similarity index 94%
rename from system/system.S
rename to system/system_asm.S
index 04ea3f4..7ab7bca 100644
--- a/system/system.S
+++ b/system/system_asm.S
@@ -8,9 +8,8 @@
 .code32
 .section ".text"
 .global start
+.extern main
 start:
-	ljmp $SEL_KERNEL_CODE,$suite
-suite:
 	movw $SEL_KERNEL_DATA, %ax
       movw %ax, %ds
       movw %ax, %es
@@ -26,3 +25,4 @@ suite:
 	xor %esi,%esi
 	xor %edi,%edi
 	xor %ebp,%ebp
+	call main