diff --git a/elec/spice/pwm/PWM.net b/elec/spice/pwm/PWM.net
new file mode 100644
index 0000000..e0b939e
--- /dev/null
+++ b/elec/spice/pwm/PWM.net
@@ -0,0 +1,16 @@
+* U:\3MIC\s2\BE-CHTI\assembleur\chti23\elec\spice\pwm\PWM.asc
+V1 Compteur 0 PULSE(0 3.3 0 5u 0 0 5u)
+C1 Filtre 0 10n
+R1 Filtre PWM 3.9k
+V2 CompValue 0 SINE(1.65 1 2k)
+B1 PWM 0 V=if(V(CompValue)>V(Compteur),3.3,0)
+;ac dec 100 1 10meg
+.tran 0 1.5m 0 0.01u
+* Compteur de l'unité Timer
+* Partie PWM de l'unité Timer
+* TIMER3
+* PB0
+* Chanel 3
+* STM32F103
+.backanno
+.end
diff --git a/soft/PjtKEIL_StepSon/Src/GestionSon.s b/soft/PjtKEIL_StepSon/Src/GestionSon.s
index 493b83b..bb3b731 100644
--- a/soft/PjtKEIL_StepSon/Src/GestionSon.s
+++ b/soft/PjtKEIL_StepSon/Src/GestionSon.s
@@ -28,42 +28,26 @@ SortieSon	dcw 0
 
 CallbackSon proc
 	;; 1. Il faut pouvoir utiliser SortieSon comme index d'iteration dans le tableau bruitverre
-	push {r4,r5,r6,r7}
-	ldr r7,=SortieSon
-	ldr r1,=LongueurSon
-	ldr r2,=Son
-	mov r3,#0
-	mov r4,#719
-	lsr r4,r4,#1
+	push {r4,r5,r6}
+	ldr r1,=SortieSon 		;sortie
+	ldr r2,=LongueurSon 	;nb de sons
+	ldr r3,=Son 			;adresse du tableau de sons
+	mov r4,#0 				;compteur
+	mov r5,#(1<<15) 		;registre pour operations
+	mov r6,#719				;sauvegarde de 719
 	
 calcul
-	ldrsh r0, [r2,r3,lsl #1]
-	;cmp r0,#0x00007FFF
-	;bgt calcul_neg
-	;faire +32768, ensuite x719, puis diviser par 2^16 
-	mov r5,#32767
-	udiv r6,r5,r4
-	mul r0,r6
-	add r0,r4
-	str r0,[r7]
-	add r3,#1
-	cmp r1,r3
-	bne calcul
-	bl fin
-	
-calcul_neg
-	mov r5,#32768
-	udiv r6,r4,r5
-	mul r0,r6
-	sub r0,r4
-	lsl r5,r0,#1
-	sub r0,r5
-	str r0,[r7]
-	add r3,#1
-	cmp r1,r3
+	ldrsh r0, [r3,r4,lsl #1]
+	;faire +32768, ensuite x719, puis diviser par 2^16
+	add r0,r5
+	mul r0,r0,r6
+	lsr r0,#16
+	str r0,[r1]
+	add r4,#1
+	cmp r2,r4
 	bne calcul
 
-fin
-	pop {r4,r5,r6,r7}
+	pop {r4,r5,r6}
+	endp 
 		
 	END	
\ No newline at end of file
diff --git a/soft/PjtKEIL_StepSon/Src/principal.c b/soft/PjtKEIL_StepSon/Src/principal.c
index 9d3e7c3..4cd54f3 100644
--- a/soft/PjtKEIL_StepSon/Src/principal.c
+++ b/soft/PjtKEIL_StepSon/Src/principal.c
@@ -1,6 +1,7 @@
 
 
 #include "DriverJeuLaser.h"
+//#include "../Driver/DriverJeuLaser.inc"
 extern void CallbackSon(void);
 extern int PeriodeSonMicroSec;
 
@@ -17,9 +18,12 @@ CLOCK_Configure();
 
 Timer_1234_Init_ff(TIM4, (1/PeriodeSonMicroSec*0.000001) );
 Active_IT_Debordement_Timer( TIM4, 2, CallbackSon );
+	
+//Timer_1234_Init_ff(TIM3, 720 );
+char GPIO_Configure(GPIOB, 0, OUTPUT, ALT_PPULL);
+PWM_Init_ff(TIM3,3,720);
+PWM_Set_Value_TIM3_Ch3(720);
 
-	
-	
 
 //============================================================================	
 	
diff --git a/soft/PjtKEIL_StepSon/StepSon.uvoptx b/soft/PjtKEIL_StepSon/StepSon.uvoptx
index 765bc55..608ab4e 100644
--- a/soft/PjtKEIL_StepSon/StepSon.uvoptx
+++ b/soft/PjtKEIL_StepSon/StepSon.uvoptx
@@ -157,9 +157,9 @@
         <Bp>
           <Number>0</Number>
           <Type>0</Type>
-          <LineNumber>37</LineNumber>
+          <LineNumber>42</LineNumber>
           <EnabledFlag>1</EnabledFlag>
-          <Address>134220580</Address>
+          <Address>134220588</Address>
           <ByteObject>0</ByteObject>
           <HtxType>0</HtxType>
           <ManyObjects>0</ManyObjects>
@@ -168,7 +168,23 @@
           <BreakIfRCount>1</BreakIfRCount>
           <Filename>.\Src\GestionSon.s</Filename>
           <ExecCommand></ExecCommand>
-          <Expression>\\StepSon\Src/GestionSon.s\37</Expression>
+          <Expression>\\StepSon\Src/GestionSon.s\42</Expression>
+        </Bp>
+        <Bp>
+          <Number>1</Number>
+          <Type>0</Type>
+          <LineNumber>38</LineNumber>
+          <EnabledFlag>1</EnabledFlag>
+          <Address>0</Address>
+          <ByteObject>0</ByteObject>
+          <HtxType>0</HtxType>
+          <ManyObjects>0</ManyObjects>
+          <SizeOfObject>0</SizeOfObject>
+          <BreakByAccess>0</BreakByAccess>
+          <BreakIfRCount>0</BreakIfRCount>
+          <Filename>.\Src\GestionSon.s</Filename>
+          <ExecCommand></ExecCommand>
+          <Expression></Expression>
         </Bp>
       </Breakpoint>
       <WatchWindow1>
@@ -187,17 +203,12 @@
           <WinNumber>1</WinNumber>
           <ItemText>r0</ItemText>
         </Ww>
-        <Ww>
-          <count>3</count>
-          <WinNumber>1</WinNumber>
-          <ItemText>r7</ItemText>
-        </Ww>
       </WatchWindow1>
       <MemoryWindow1>
         <Mm>
           <WinNumber>1</WinNumber>
           <SubType>0</SubType>
-          <ItemText>r7</ItemText>
+          <ItemText>r3</ItemText>
           <AccSizeX>0</AccSizeX>
         </Mm>
       </MemoryWindow1>
@@ -271,7 +282,7 @@
         <Wi>
           <IntNumber>0</IntNumber>
           <FirstString>`SortieSon</FirstString>
-          <SecondString>FF0000000000000000000000000000000080864000000000000000000000000000000000536F72746965536F6E00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000700000001000000000000000000F03F1000000000000000000000000000000000000000C40A0008</SecondString>
+          <SecondString>FF0000000000000000000000000000000078864000000000000000000000000000000000536F72746965536F6E00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000700000001000000000000000000F03F1000000000000000000000000000000000000000C40A0008</SecondString>
         </Wi>
       </LogicAnalyzers>
       <DebugDescription>