diff --git a/include/asm.h b/include/asm.h
index aabe01e..111727a 100755
--- a/include/asm.h
+++ b/include/asm.h
@@ -41,6 +41,10 @@
 
 #define ltr(tss) asm volatile ("ltr %%ax":: "a" (tss))
 
+#define str(tss) asm volatile ("str %%ax;\
+                                mov %%ax,%0":: "m" (tss))
+
+
 /******************************************************************************/
 
 #define outb(port,value) \
diff --git a/include/cpu.h b/include/cpu.h
index 1cf59f8..1de28c7 100755
--- a/include/cpu.h
+++ b/include/cpu.h
@@ -43,5 +43,6 @@ bool cansetflag (u32 flag);
 void cpuid(u32 op, u32 *eax, u32 *ebx,u32 *ecx, u32 *edx);
 u8 getcpuinfos(cpuinfo *inf);
 u32 getESP(void);
-void dump_regs(exception_stack *stack);
-
+u32 setESP(u32 stack);
+void dump_cpu(save_stack *stack);
+void show_cpu(save_stack *stack);
diff --git a/include/gdt.h b/include/gdt.h
index fff1490..75a9032 100755
--- a/include/gdt.h
+++ b/include/gdt.h
@@ -77,3 +77,11 @@ typedef struct tss {
 void inittr(void);
 void initgdt(u32 offset);
 void makegdtdes(u32 base, u32 limite, u8 acces, u8 flags, gdtdes *desc);
+u32 getdesbase(u16 sel);
+u8 getdestype(u16 sel);
+u32 getdessize(u16 sel);
+u32 getdeslimit(u16 sel);
+bool isdesvalid(u16 sel);
+u8 getdesbit3(u16 sel);
+u32 getdesdpl(u16 sel);
+u16 getdesalign(u16 sel);
diff --git a/include/interrupts.h b/include/interrupts.h
index 63277ff..3cfeb7d 100755
--- a/include/interrupts.h
+++ b/include/interrupts.h
@@ -37,6 +37,29 @@
 #define TIMER_FREQ     1193180 /* fréquence pour timer dans un PC ou AT */
 #define HZ             100  /* Fréquence d'horloge (ajutste logiciellement sur IBM-PC) */
 
+/* save pile */
+typedef struct save_stack {
+   u32 cr4;
+   u32 cr3;
+   u32 cr2;
+   u32 cr0;
+   u32 eflags;
+   u32 ss;
+   u32 gs;
+   u32 fs;
+   u32 es;
+   u32 ds;
+   u32 eip;
+   u32 cs;
+   u32 esp;
+   u32 ebp;
+   u32 edi;
+   u32 esi;
+   u32 edx;
+   u32 ecx;
+   u32 ebx;
+   u32 eax;
+} save_stack __attribute__ ((packed));
 /* exception pile */
 typedef struct exception_stack {
     u32 error_code;
@@ -72,7 +95,7 @@ struct idtr {
  void initpic(void);
  void enableirq(u8 irq);
  void disableirq(u8 irq);
- void cpuerror(const u8 * src, const exception_stack *stack);
+ void cpuerror(const u8 * src, const save_stack *stack);
 
 #endif
 
diff --git a/include/shell.h b/include/shell.h
index 3b5fee8..421b0ca 100644
--- a/include/shell.h
+++ b/include/shell.h
@@ -17,4 +17,6 @@ int mode();
 int clear();
 int regs();
 int info();
-int pagefault();
+int pgfaultr();
+int pgfaultw();
+int divzerr();
diff --git a/lib/cpu.c b/lib/cpu.c
index 9349540..f26422d 100755
--- a/lib/cpu.c
+++ b/lib/cpu.c
@@ -6,6 +6,7 @@
 #include "memory.h"
 #include "string.h"
 #include "asm.h"
+#include "gdt.h"
 
 /* Technologies supportées */
 
@@ -135,103 +136,99 @@ u32 getESP(void)
 	return stack;
 }
 
+/******************************************************************************/
+/* Fixe la tête de pile */
+
+u32 setESP(u32 stack)
+{
+    asm("movl %[param],%%esp;": [param] "=r"(stack));
+}
+
+/******************************************************************************/
+/* Sauvegarde les registres CPU */
+
+void dump_cpu(save_stack *stack)
+{
+save_stack new;
+asm("   addl $0x50,%%esp \n \
+        pushl %%eax \n \
+        pushl %%ebx \n \
+        pushl %%ecx \n \
+        pushl %%edx \n \
+        pushl %%esi \n \
+        pushl %%edi \n \
+        pushl %%ebp \n \
+        pushl %%esp \n \
+        pushl %%cs \n \
+        pushl 0x0 \n \
+        pushl %%ds \n \
+        pushl %%es \n \
+        pushl %%fs \n \
+        pushl %%gs \n \
+        pushl %%ss \n \
+        pushf \n \
+        mov %%cr0, %%ebx \n \
+        pushl %%ebx\n \
+        mov %%cr2, %%ebx \n \
+        pushl %%ebx\n \
+        mov %%cr3, %%ebx \n \
+        pushl %%ebx\n \
+        mov %%cr4, %%ebx \n \
+        pushl %%ebx":::);
+    memcpy(&new, stack, sizeof(save_stack), 1);
+}
 
 /******************************************************************************/
 /* Affiche les registres CPU */
 
-void dump_regs(exception_stack *stack)
+void show_cpu(save_stack *stack)
 {
-	cli();
-	u32 eax = 0;
-	u32 ebx = 0;
-	u32 ecx = 0;
-	u32 edx = 0;
-	u32 esi = 0;
-	u32 edi = 0;
-	u32 ebp = 0;
-	u32 esp = 0;
-	u32 eip = 0;
-	u16 cs = 0;
-	u16 ds = 0;
-	u16 es = 0;
-	u16 fs = 0;
-	u16 gs = 0;
-	u16 ss = 0;
-	u32 cr0 = 0;
-	u32 cr1 = 0;
-	u32 cr2 = 0;
-	u32 cr3 = 0;
-	u32 cr4 = 0;
-	u32 eflags = 0;
- asm("movl %%eax, %[a1] ;" "movl %%ebx, %[b1] ;" "movl %%ecx, %[c1] ;" "movl %%edx, %[d1] ;" "movl %%esi, %[e1] ;" "movl %%edi, %[f1] ;" "movl %%esp, %[g1] ;" "movl %%ebp, %[h1] ;" "movw %%cs, %[i1] ;" "movw %%ds, %[j1] ;" "movw %%es, %[k1] ;" "movw %%fs, %[l1] ;" "movw %%gs, %[m1] ;" "movw %%ss, %[n1] ;" "mov %%cr0, %%eax ;" "mov %%eax, %[o1] ;" "mov %%cr2, %%eax ;" "mov %%eax, %[p1] ;" "mov %%cr3, %%eax ;" "mov %%eax, %[q1] ;" "mov %%cr4, %%eax ;" "mov %%eax,%[r1] ;":
-[a1] "=m"(eax),[b1] "=m"(ebx),[c1] "=m"(ecx),[d1] "=m"(edx),[e1] "=m"(esi),
-[f1] "=m"(edi),[g1] "=m"(esp),[h1] "=m"(ebp),[i1] "=m"(cs),[j1] "=m"(ds),
-[k1] "=m"(es),[l1] "=m"(fs),[m1] "=m"(gs),[n1] "=m"(ss),[o1] "=m"(cr0),
-[p1] "=m"(cr2),[q1] "=m"(cr3),[r1] "=m"(cr4));
-    if (stack!=0) {
-        eip=stack->eip;
-        eflags=stack->eflags;
-        cs=stack->cs;
-        esp=stack;
-        printf("\033[0m");
-    }
-    else
-    printf("\033[1mATTENTION PAS DE PILE ! REGISTRES INCERTAINS\r\n");
-	printf("EAX=%X EBX=%X ECX=%X EDX=%X\r\n", eax, ebx, ecx, edx);
-	printf("ESI=%X EDI=%X ESP=%X EBP=%X\r\n", esi, edi, esp, ebp);
-	printf("EIP=%X\r\n", eip);
-	printf
-	    ("CS=%hX  DS=%hX  ES=%hX  FS=%hX  GS=%hX  SS=%hX\r\n",
-	     (u32) cs, (u32) ds, (u32) es, (u32) fs, (u32) gs, (u32) ss);
-	printf("CR0=%X CR1=N/A       CR2=%X CR3=%X CR4=%X\r\n", cr0, cr2, cr3,
-	       cr4);
-
- asm("pushf      ;" "pop %[f1] ;":
-[f1] "=m"(eflags));
-
-	printf("EFLAGS=%X", eflags);
-
-	if (eflags & (1 << 0))	// Carry
-		printf(" (C1");
-	else
-		printf(" (C0");
-
-	if (eflags & (1 << 2))	// Parity
-		printf(" P1");
-	else
-		printf(" P0");
-
-	if (eflags & (1 << 4))	// Adjust
-		printf(" A1");
-	else
-		printf(" A0");
-
-	if (eflags & (1 << 6))	// Zero
-		printf(" Z1");
-	else
-		printf(" Z0");
-
-	if (eflags & (1 << 7))	// Sign
-		printf(" S1");
-	else
-		printf(" S0");
-
-	if (eflags & (1 << 11))	// Overflow
-		printf(" O1)\r\n");
-	else
-		printf(" O0)\r\n");
+	printf("EAX=%Y EBX=%Y ECX=%Y EDX=%Y\r\n", stack->eax, stack->ebx, stack->ecx, stack->edx);
+	printf("ESI=%Y EDI=%Y ESP=%Y EBP=%Y\r\n", stack->esi, stack->edi, stack->esp, stack->ebp);
+	printf("EIP=%Y EFL=%Y [%c%c%c%c%c%c%c%c%c]\r\n", stack->eip, stack->eflags,
+    (stack->eflags & (1 <<11)) ? 'O':'-',
+    (stack->eflags & (1 <<10)) ? 'D':'-',
+    (stack->eflags & (1 << 9)) ? 'I':'-',
+    (stack->eflags & (1 << 8)) ? 'T':'-',
+    (stack->eflags & (1 << 7)) ? 'S':'-',
+    (stack->eflags & (1 << 6)) ? 'Z':'-',
+    (stack->eflags & (1 << 4)) ? 'A':'-',
+    (stack->eflags & (1 << 2)) ? 'P':'-',
+    (stack->eflags & (1 << 0)) ? 'C':'-');
+	printf("CS =%hY %Y %Y DPL=%d %cS%d [%c%c%c] %h ub\r\n",stack->cs,getdesbase(stack->cs),getdeslimit(stack->cs),getdesdpl(stack->cs),getdestype(stack->cs),getdessize(stack->cs),getdesbit3(stack->cs),getdesbit2(stack->cs),getdesbit1(stack->cs),getdesalign(stack->cs));
+	printf("DS =%hY %Y %Y DPL=%d %cS%d [%c%c%c] %h ub\r\n",stack->ds,getdesbase(stack->ds),getdeslimit(stack->ds),getdesdpl(stack->ds),getdestype(stack->ds),getdessize(stack->ds),getdesbit3(stack->ds),getdesbit2(stack->ds),getdesbit1(stack->ds),getdesalign(stack->ds));
+	printf("SS =%hY %Y %Y DPL=%d %cS%d [%c%c%c] %h ub\r\n",stack->ss,getdesbase(stack->ss),getdeslimit(stack->ss),getdesdpl(stack->ss),getdestype(stack->ss),getdessize(stack->ss),getdesbit3(stack->ss),getdesbit2(stack->ss),getdesbit1(stack->ss),getdesalign(stack->ss));
+	printf("ES =%hY %Y %Y DPL=%d %cS%d [%c%c%c] %h ub\r\n",stack->es,getdesbase(stack->es),getdeslimit(stack->es),getdesdpl(stack->es),getdestype(stack->es),getdessize(stack->es),getdesbit3(stack->es),getdesbit2(stack->es),getdesbit1(stack->es),getdesalign(stack->es));
+	printf("FS =%hY %Y %Y DPL=%d %cS%d [%c%c%c] %h ub\r\n",stack->fs,getdesbase(stack->fs),getdeslimit(stack->fs),getdesdpl(stack->fs),getdestype(stack->fs),getdessize(stack->fs),getdesbit3(stack->fs),getdesbit2(stack->fs),getdesbit1(stack->fs),getdesalign(stack->fs));
+	printf("GS =%hY %Y %Y DPL=%d %cS%d [%c%c%c] %h ub\r\n",stack->gs,getdesbase(stack->gs),getdeslimit(stack->gs),getdesdpl(stack->gs),getdestype(stack->gs),getdessize(stack->gs),getdesbit3(stack->gs),getdesbit2(stack->gs),getdesbit1(stack->gs),getdesalign(stack->gs));
+    u32 tss;
+    str(tss);
+    printf("TR =%hY %Y %Y DPL=%d %cS%d [%c%c%c] %h ub\r\n",stack->gs,getdesbase(tss),getdeslimit(tss),getdesdpl(tss),getdestype(tss),getdessize(tss),getdesbit3(tss),getdesbit2(tss),getdesbit1(tss),getdesalign(tss));
+	struct gdtr gdtreg;
+	sgdt(&gdtreg);
+     printf("GDT=     %Y %Y\r\n",gdtreg.base,gdtreg.limite);
+	struct idtr idtreg;
+	sidt(&idtreg);
+     printf("IDT=     %Y %Y\r\n",idtreg.base,idtreg.limite);
 
 	printf("STACK\r\n");
-	u32 i = 0;
-	for (u32 *pointer = esp; pointer < KERNEL_STACK_ADDR; pointer += 4) {
-		printf("+%d:%X\t\t%X\r\n", i++, pointer,
-		       (u32)(*pointer));
-		if (i > 5) {
-			print("...\r\n");
-			break;
-		}
+    if (abs(KERNEL_STACK_ADDR-stack->esp)>0x10000)
+        printf("Pile invalide !");
+    else
+    {
+        u32 i=0;
+	    for (u32 *pointer = stack->esp; pointer < KERNEL_STACK_ADDR; pointer ++) {
+            if (i>0 && i % 10 == 0) print("\033[10A");
+            if (i>=10)
+                print("\033[25C");            
+		    printf("+%d:%Y - %Y\r\n", i++, pointer, (u32)(*pointer));
+		    if (i > 20) {
+			    print("...\r\n");
+			    break;
+		    }
+        }
+        for(u32 j=0;j<10-(i % 10);j++)
+            print("\033[01B");
 	}
-    printf("\033[0m");
-	sti();
 }
 /*******************************************************************************/
diff --git a/lib/gdt.c b/lib/gdt.c
index 77c12b7..95a668f 100755
--- a/lib/gdt.c
+++ b/lib/gdt.c
@@ -74,6 +74,122 @@ void initselectors(u32 executingoffset)
             ret\n"::[data] "i"(SEL_KERNEL_DATA),[code] "i"(SEL_KERNEL_CODE),[stack] "i"(SEL_KERNEL_STACK),[stackoff] "i"(KERNEL_STACK_ADDR),[offset] "m"(executingoffset));
 }
 
+/*******************************************************************************/
+/* récupère la base d'un descripteur GDT */
+
+u32 getdesbase(u16 sel)
+{
+    gdtdes *entry=GDT_ADDR;
+    u8 index=sel/sizeof(gdtdes);
+    return (entry[index].base0_15+(entry[index].base16_23<<16)+(entry[index].base24_31<<24));
+}
+
+/*******************************************************************************/
+/* récupère la limite d'un descripteur GDT */
+
+u32 getdeslimit(u16 sel)
+{
+    gdtdes *entry=GDT_ADDR;
+    u8 index=sel/sizeof(gdtdes);
+    return (entry[index].lim0_15+(entry[index].lim16_19<<16));
+}
+
+/*******************************************************************************/
+/* récupère la limite d'un descripteur GDT */
+
+u32 getdesdpl(u16 sel)
+{
+    gdtdes *entry=GDT_ADDR;
+    u8 index=sel/sizeof(gdtdes);
+    return (entry[index].acces>>5 & 0b11);
+}
+
+/*******************************************************************************/
+/* récupère le type d'un descripteur GDT */
+
+u8 getdestype(u16 sel)
+{
+    gdtdes *entry=GDT_ADDR;
+    u8 index=sel/sizeof(gdtdes);
+    if (((entry[index].acces & 0b10100) == 0) && ((entry[index].acces & 0b01000) > 0) && ((entry[index].acces & 0b0001) > 0) && ((entry[index].flags & 0b0110) == 0))
+        return 'T';
+    else
+        return (((entry[index].acces & 0b1000) > 0) ? 'C' : 'D');
+}
+
+/*******************************************************************************/
+/* récupère l'info 1 d'un descripteur GDT */
+
+u8 getdesbit1(u16 sel)
+{
+    gdtdes *entry=GDT_ADDR;
+    u8 index=sel/sizeof(gdtdes);
+    if (((entry[index].acces & 0b10100) == 0) && ((entry[index].acces & 0b01000) > 0) && ((entry[index].acces & 0b0001) > 0) && ((entry[index].flags & 0b0110) == 0))
+    return (((entry[index].acces & 0b10) > 0) ? 'B' : '-');        
+        else
+    return (((entry[index].acces & 0b1) > 0) ? 'A' : '-');        
+}
+
+/*******************************************************************************/
+/* récupère l'info 2 d'un descripteur GDT */
+
+u8 getdesbit2(u16 sel)
+{
+    gdtdes *entry=GDT_ADDR;
+    u8 index=sel/sizeof(gdtdes);
+    if (((entry[index].acces & 0b10100) == 0) && ((entry[index].acces & 0b01000) > 0) && ((entry[index].acces & 0b0001) > 0) && ((entry[index].flags & 0b0110) == 0))
+        return (((entry[index].flags & 0b1) > 0) ? 'U' : '-');        
+    else if ((entry[index].acces & 0b1000) > 0)
+        return (((entry[index].acces & 0b10) > 0) ? 'R' : '-');
+    else
+        return (((entry[index].acces & 0b10) > 0) ? 'W' : 'R');         
+}
+
+/*******************************************************************************/
+/* récupère l'info 3 d'un descripteur GDT */
+
+u8 getdesbit3(u16 sel)
+{
+    gdtdes *entry=GDT_ADDR;
+    u8 index=sel/sizeof(gdtdes);
+    if ((entry[index].acces & 0b1000) > 0)
+        return (((entry[index].acces & 0b100) > 0) ? 'C' : '-');
+    else
+        return (((entry[index].acces & 0b100) > 0) ? 'D' : 'U');           
+}
+
+/*******************************************************************************/
+/* récupère l'alignement d'un descripteur GDT */
+
+u16 getdesalign(u16 sel)
+{
+    gdtdes *entry=GDT_ADDR;
+    u8 index=sel/sizeof(gdtdes);
+    return (((entry[index].flags & 0b1000) > 0) ? 4096: 1);           
+}
+
+/*******************************************************************************/
+/* récupère si descripteur GDT est valide */
+
+bool isdesvalid(u16 sel)
+{
+    gdtdes *entry=GDT_ADDR;
+    u8 index=sel/sizeof(gdtdes);
+    return ((entry[index].acces & 0b10000000) > 0);
+}
+
+/*******************************************************************************/
+/* récupère la dimension d'un descripteur GDT */
+
+u32 getdessize(u16 sel)
+{
+    gdtdes *entry=GDT_ADDR;
+    u8 index=sel/sizeof(gdtdes);
+    if (((entry[index].acces & 0b10100) == 0) && ((entry[index].acces & 0b01000) > 0) && ((entry[index].acces & 0b0001) > 0) && ((entry[index].flags & 0b0110) == 0))
+        return 32;
+    else
+        return (((entry[index].flags & 0b1000) > 0) ? 32 : 16);
+}
 /*******************************************************************************/
 /* Créé un descripteur GDT */
 
diff --git a/lib/interrupts.c b/lib/interrupts.c
index d94e8db..423a571 100755
--- a/lib/interrupts.c
+++ b/lib/interrupts.c
@@ -136,11 +136,12 @@ void putidt(u32 offset, u16 select, u16 type, u16 index)
 /******************************************************************************/
 /* Affiche une erreur CPU et fige l'ordinateur */
 
-void cpuerror(const u8 * src, const exception_stack *stack)
+void cpuerror(const u8 * src, const save_stack *stack)
 {
 	printf("\033[31m*** ERREUR CPU : %s *** \r\n", src);
-	dump_regs(stack);
-	print("<Appuyer une touche pour continuer>\r\n");
+	show_cpu(stack);
+	print("<Appuyer une touche pour continuer>\033[0m\r\n");
+    sti();
     waitascii();
     initselectors(retry_address);
 	/*while (true) {
@@ -168,79 +169,90 @@ void interruption()
 
 void exception0()
 {
-	cpuerror("divide error",0x0);
+    save_stack dump;
+    exception_stack_noerror *current = getESP()+0x80;
+    dump_cpu(&dump);
+    dump.eip=current->eip;
+    dump.cs=current->cs;
+    dump.esp=(current+1);
+	cpuerror("divide error",&dump);
 }
 
 void exception1()
 {
-	cpuerror("debug exception",0x0);
+	cpuerror("debug exception",NULL);
 }
 
 void exception2()
 {
-	cpuerror("non-maskable hardware interrupt",0x0);
+	cpuerror("non-maskable hardware interrupt",NULL);
 }
 
 void exception3()
 {
-	cpuerror("INT3 instruction",0x0);
+	cpuerror("INT3 instruction",NULL);
 }
 
 void exception4()
 {
-	cpuerror("INTO instruction detected overflow",0x0);
+	cpuerror("INTO instruction detected overflow",NULL);
 }
 
 void exception5()
 {
-	cpuerror("BOUND instruction detected overrange",0x0);
+	cpuerror("BOUND instruction detected overrange",NULL);
 }
 
 void exception6()
 {
-	cpuerror("invalid instruction opcode",0x0);
+	cpuerror("invalid instruction opcode",NULL);
 }
 
 void exception7()
 {
-	cpuerror("no coprocessor",0x0);
+	cpuerror("no coprocessor",NULL);
 }
 
 void exception8()
 {
-	cpuerror("double fault",0x0);
+	cpuerror("double fault",NULL);
 }
 
 void exception9()
 {
-	cpuerror("coprocessor segment overrun",0x0);
+	cpuerror("coprocessor segment overrun",NULL);
 }
 
 void exception10()
 {
-	cpuerror("invalid task state segment (TSS)",0x0);
+	cpuerror("invalid task state segment (TSS)",NULL);
 }
 
 void exception11()
 {
-	cpuerror("segment not present",0x0);
+	cpuerror("segment not present",NULL);
 }
 
 void exception12()
 {
-	cpuerror("stack fault",0x0);
+	cpuerror("stack fault",NULL);
 }
 
 void exception13()
 {
-	cpuerror("general protection fault (GPF)",0x0);
+	cpuerror("general protection fault (GPF)",NULL);
 }
 
 void exception14()
 {
-    exception_stack *stack = getESP()+0x30;
-    u8 *errorstring;
-    switch (stack->error_code) {
+    save_stack dump;
+    exception_stack *current = getESP()+0x80;
+    dump_cpu(&dump);
+    dump.eip=current->eip;
+    dump.cs=current->cs;
+    dump.esp=(current+1);
+    u8 *errorstring="page fault";
+    switch (current->error_code) {
         case 0:
             errorstring="page fault - Supervisory process tried to read a non-present page entry";
             break;
@@ -266,27 +278,27 @@ void exception14()
             errorstring="Page fault - User process tried to write a page and caused a protection fault";
             break;   
     }
-	cpuerror(errorstring,stack);
+	cpuerror(errorstring,&dump);
 }
 
 void exception15()
 {
-	cpuerror("(reserved)",0x0);
+	cpuerror("(reserved)",NULL);
 }
 
 void exception16()
 {
-	cpuerror("coprocessor error",0x0);
+	cpuerror("coprocessor error",NULL);
 }
 
 void exception17()
 {
-	cpuerror("alignment check",0x0);
+	cpuerror("alignment check",NULL);
 }
 
 void exception18()
 {
-	cpuerror("machine check",0x0);
+	cpuerror("machine check",NULL);
 }
 
 /******************************************************************************/
diff --git a/lib/keyboard.c b/lib/keyboard.c
index c81af97..7e86c4c 100755
--- a/lib/keyboard.c
+++ b/lib/keyboard.c
@@ -218,7 +218,9 @@ unsigned convert(u32 keypressed)
 	}
 
 	else if (key == SCAN_F9) {
-		dump_regs();
+        save_stack dump;
+        dump_cpu(&dump);
+        show_cpu(&dump);
 	}
 
 	else if (key == SCAN_F10) {
diff --git a/lib/shell.c b/lib/shell.c
index 6cb8f62..3292cfa 100644
--- a/lib/shell.c
+++ b/lib/shell.c
@@ -22,7 +22,10 @@ static command commands[] = {
 	{"GDT"       , "", &readgdt},
 	{"IDT"       , "", &readidt},
 	{"INFO"      , "", &info},
-    {"PAGEFAULT" , "", &pagefault}
+    {"PGFAULTW" , "", &pgfaultw},
+    {"PGFAULTR" , "", &pgfaultr},
+    {"DIVZERR" , "", &divzerr}
+
 };
 
 /*******************************************************************************/
@@ -56,13 +59,28 @@ void shell()
 	}
 }
 
+/*******************************************************************************/
+/* Génère une erreur de division par 0 */
+int divzerr()
+{
+	print("Creation d'une erreur de division par 0 !\r\n");
+    asm("movl $0x0,%ecx; divl %ecx");
+}
+
 /*******************************************************************************/
 /* Génère une erreur de page à l'adresse 0xE0000000 */
-int pagefault()
+int pgfaultw()
 {
 	print("Creation d'une erreur de page !\r\n");
-    asm("mov $0x66666666, %eax \n \
-		mov %eax,0xE0000000");
+    asm("movl $0x66666666,(0xE0000000)");
+}
+
+/*******************************************************************************/
+/* Génère une erreur de page à l'adresse 0xD0000000 */
+int pgfaultr()
+{
+	print("Creation d'une erreur de page !\r\n");
+    asm("movl (0xD0000000),%eax");
 }
 
 /*******************************************************************************/
@@ -78,7 +96,9 @@ int info()
 
 int regs()
 {
-	dump_regs(0x0);
+    save_stack dump;
+    dump_cpu(&dump);
+    show_cpu(&dump);
 	return 0;
 }
 
diff --git a/lib/video.c b/lib/video.c
index 3fd6c5b..a43aec2 100755
--- a/lib/video.c
+++ b/lib/video.c
@@ -463,6 +463,8 @@ u32 printf(const u8 * string, ...)
 				break;
 			case 'x':
 			case 'X':
+			case 'y':
+			case 'Y':
                 if (asize==0)
 				    num = (u64) va_arg(args, u8);
                 else if (asize==1)
@@ -474,9 +476,9 @@ u32 printf(const u8 * string, ...)
 				if (charadd == 0xFF)
 					charadd = '0';
 				itoa(num, &buffer, 16, sizes[asize], charadd);
-				if (achar == 'X')
+				if (achar == 'X'||achar == 'Y')
 					strtoupper(&buffer);
-				print(&strbase16);
+				if (achar == 'X') print(&strbase16);
 				counter += print(&buffer) + 1;
 				flag = false;
 				break;