diff --git a/module01/ex01/main.c b/module01/ex01/main.c
index 6c2c33c..e60fb16 100644
--- a/module01/ex01/main.c
+++ b/module01/ex01/main.c
@@ -51,25 +51,21 @@
 int main() {
 	MODE_OUTPUT(B, D2);
 
-	TCCR1B |= (1 << WGM12);						// set timer in CTC (Clear Time on Compare) mode
-												//   -> Table 16-4 : use bit WGM12 to set mode ctc
-												//   -> 16.11.2 : bit WGM12 is located in register TCCR1B
+	TCCR1B |= (1 << WGM12);				// set timer in CTC (Clear Time on Compare) mode
+										//   -> Table 16-4 : use bit WGM12 to set mode ctc
+										//   -> 16.11.2 : bit WGM12 is located in register TCCR1B
 
-	OCR1A = TIME_MS(500);						// set CTC compare value
-												//   -> Table 16-4 : the value to reset the timer is the Output Compare Registers OCR1A
+	TCCR1A |= (1 << COM1A0 ) ;			// Enable timer 1 Compare Output channel A in toggle mode
+										//   -> Table 14-3 : alternate functions for PORTB1 is OC1A (Timer/Counter1 Output Compare Match A Output)
+										//   -> 14.3.1 : OC1A/PCINT1 – Port B, Bit 1
+
+	OCR1A = TIME_MS(500);				// set CTC compare value
+										//   -> Table 16-4 : the value to reset the timer is the Output Compare Registers OCR1A
 
 	TCCR1B |= (PRESCALE_SET);
 
 	while(1) {
-		if (TIFR1 & (1 << OCF1A)) {				// when comparison has occured, bit OCF1A is set
-												//    -> 16.2.1 : "The compare match event will also set the Compare Match Flag (OCF1A/B) which can be used to generate an Output Compare interrupt request"
-												//    -> 16.11.9 : bit OCF1A is in register TIFR1
-
-			TOGGLE_LED(D2);						// toggle using PINx register
-
-			TIFR1 = (1 << OCF1A);				// clear the CTC flag
-												//    -> 16.11.9 : "OCF1A can be cleared by writing a logic one to its bit location"
-		}
+		continue;
 	}
 }