diff --git a/EmbeddedSystemsTHM/EmbeddedSystemsTHM.cproj b/EmbeddedSystemsTHM/EmbeddedSystemsTHM.cproj
index bccc70a..4555e20 100644
--- a/EmbeddedSystemsTHM/EmbeddedSystemsTHM.cproj
+++ b/EmbeddedSystemsTHM/EmbeddedSystemsTHM.cproj
@@ -43,15 +43,15 @@
     </com_atmel_avrdbg_tool_simulator>
     <AsfFrameworkConfig>
       <framework-data xmlns="">
-  <options />
-  <configurations />
-  <files />
-  <documentation help="" />
-  <offline-documentation help="" />
-  <dependencies>
-    <content-extension eid="atmel.asf" uuidref="Atmel.ASF" version="3.49.1" />
-  </dependencies>
-</framework-data>
+        <options />
+        <configurations />
+        <files />
+        <documentation help="" />
+        <offline-documentation help="" />
+        <dependencies>
+          <content-extension eid="atmel.asf" uuidref="Atmel.ASF" version="3.49.1" />
+        </dependencies>
+      </framework-data>
     </AsfFrameworkConfig>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)' == 'Release' ">
@@ -150,6 +150,12 @@
     <Compile Include="Taster.h">
       <SubType>compile</SubType>
     </Compile>
+    <Compile Include="Timer.c">
+      <SubType>compile</SubType>
+    </Compile>
+    <Compile Include="Timer.h">
+      <SubType>compile</SubType>
+    </Compile>
   </ItemGroup>
   <Import Project="$(AVRSTUDIO_EXE_PATH)\\Vs\\Compiler.targets" />
 </Project>
\ No newline at end of file
diff --git a/EmbeddedSystemsTHM/Led.c b/EmbeddedSystemsTHM/Led.c
index 30004b9..2dd0f82 100644
--- a/EmbeddedSystemsTHM/Led.c
+++ b/EmbeddedSystemsTHM/Led.c
@@ -1,62 +1,80 @@
 #include <avr/io.h>
 
-void Led_init(void){
+void 
+Led_init (void){
 	DDRB = 0xFF;		// Set all bits in the B Data-Direction Register to output
 	PORTB = 0x00;		// Set all bits in the PORT B Register to low to turn all LEDs off
 }
 
-void Led1_On(void){
+void 
+Led1_On (void){
 	PORTB |= (1<<7);	// Set the bit for LED_1 to hight to turn it on
 }
-void Led1_Off(void){
+void
+ Led1_Off (void){
 	PORTB &= ~(1<<7);	// Set the bit for LED_1 to low to turn it off
 }
 
-void Led2_On(void){
+void 
+Led2_On (void){
 	PORTB |= (1<<6);
 }	
-void Led2_Off(void){
+void 
+Led2_Off (void){
 	PORTB &= ~(1<<6);
 }
 
-void Led3_On(void){
+void 
+Led3_On (void){
 	PORTB |= (1<<5);
 }
-void Led3_Off(void){
+void 
+Led3_Off (void){
 	PORTB &= ~(1<<5);
 }
 
-void Led4_On(void){
+void 
+Led4_On (void){
 	PORTB |= (1<<4);
 }
-void Led4_Off(void){
+void
+ 
+ Led4_Off (void){
 	PORTB &= ~(1<<4);
 }
 
-void Led5_On(void){
+void 
+Led5_On (void){
 	PORTB |= (1<<3);
 }
-void Led5_Off(void){
+void 
+Led5_Off (void){
 	PORTB &= ~(1<<3);
 }
 
-void Led6_On(void){
+void 
+Led6_On (void){
 	PORTB |= (1<<2);
 }
-void Led6_Off(void){
+void 
+Led6_Off (void){
 	PORTB &= ~(1<<2);
 }
 
-void Led7_On(void){
+void 
+Led7_On (void){
 	PORTB |= (1<<1);
 }
-void Led7_Off(void){
+void 
+Led7_Off (void){
 	PORTB &= ~(1<<1);
 }
 
-void Led8_On(void){
+void 
+Led8_On (void){
 	PORTB |= (1<<0);
 }
-void Led8_Off(void){
+void 
+Led8_Off (void){
 	PORTB &= ~(1<<0);
 }
\ No newline at end of file
diff --git a/EmbeddedSystemsTHM/Led.h b/EmbeddedSystemsTHM/Led.h
index 072924e..126bdcb 100644
--- a/EmbeddedSystemsTHM/Led.h
+++ b/EmbeddedSystemsTHM/Led.h
@@ -5,33 +5,33 @@
 /*
 Initialisiert die Hardware für die Led
 */
-void Led_init(void);
+void Led_init (void);
 
 /*
 Funktionen schalten entsprechende LEDs ein oder aus.
 */
-void Led1_On(void);
-void Led1_Off(void);
+void Led1_On (void);
+void Led1_Off (void);
 
-void Led2_On(void);
-void Led2_Off(void);
+void Led2_On (void);
+void Led2_Off (void);
 
-void Led3_On(void);
-void Led3_Off(void);
+void Led3_On (void);
+void Led3_Off (void);
 
-void Led4_On(void);
-void Led4_Off(void);
+void Led4_On (void);
+void Led4_Off (void);
 
-void Led5_On(void);
-void Led5_Off(void);
+void Led5_On (void);
+void Led5_Off (void);
 
-void Led6_On(void);
-void Led6_Off(void);
+void Led6_On (void);
+void Led6_Off (void);
 
-void Led7_On(void);
-void Led7_Off(void);
+void Led7_On (void);
+void Led7_Off (void);
 
-void Led8_On(void);
-void Led8_Off(void);
+void Led8_On (void);
+void Led8_Off (void);
 
 #endif /* LED_H_ */
\ No newline at end of file
diff --git a/EmbeddedSystemsTHM/Taster.c b/EmbeddedSystemsTHM/Taster.c
index 19278fb..772c30b 100644
--- a/EmbeddedSystemsTHM/Taster.c
+++ b/EmbeddedSystemsTHM/Taster.c
@@ -1,6 +1,7 @@
 #include <avr/io.h>
 
-void Taster_init(void){
+void 
+Taster_init (void){
 	DDRD &= ~(0b111<<5);	// Set bit 5-7 of Data Direction Register D as input
 	DDRC &= ~(1<<2);		// Set bit 2 of Data Direction Register C as input
 	
@@ -8,15 +9,19 @@ void Taster_init(void){
 	PORTC |= (1<<2);		// Initialize bit 2 of PORTC as for pull up resistor
 }
 
-uint8_t Taster1_get(void){
+uint8_t 
+Taster1_get (void){
 	return ((PIND & (1<<PIND7)) == 0);
 }
-uint8_t Taster2_get(void){
+uint8_t 
+Taster2_get (void){
 	return ((PIND & (1<<PIND6)) == 0);
 }
-uint8_t Taster3_get(void){
+uint8_t 
+Taster3_get (void){
 	return ((PIND & (1<<PIND5)) == 0);
 }
-uint8_t Taster4_get(void){
+uint8_t 
+Taster4_get (void){
 	return ((PINC & (1<<PINC2)) == 0);
 }
\ No newline at end of file
diff --git a/EmbeddedSystemsTHM/Taster.h b/EmbeddedSystemsTHM/Taster.h
index 208a5bb..304fc24 100644
--- a/EmbeddedSystemsTHM/Taster.h
+++ b/EmbeddedSystemsTHM/Taster.h
@@ -6,16 +6,16 @@
 /*
 Initialisiert die Hardware für die Taster
 */
-void Taster_init(void);
+void Taster_init (void);
 
 /*
 Gibt den aktuellen Status der Tasten aus.
 Rückgabewert 0 = Taster nicht gedr�ckt, 1 = Taster gedr�ckt.
 */
-uint8_t Taster1_get(void);
-uint8_t Taster2_get(void);
-uint8_t Taster3_get(void);
-uint8_t Taster4_get(void);
+uint8_t Taster1_get (void);
+uint8_t Taster2_get (void);
+uint8_t Taster3_get (void);
+uint8_t Taster4_get (void);
 
 
 #endif /* TASTER_H_ */
\ No newline at end of file
diff --git a/EmbeddedSystemsTHM/Timer.c b/EmbeddedSystemsTHM/Timer.c
new file mode 100644
index 0000000..969177b
--- /dev/null
+++ b/EmbeddedSystemsTHM/Timer.c
@@ -0,0 +1,40 @@
+/*
+ * Timer.c
+ *
+ * Created: 28/10/2021 17:51:29
+ *  Author: n0x
+ */ 
+
+#include <avr/io.h>
+#include <avr/interrupt.h>
+
+volatile uint16_t cntr = 0;
+
+void 
+Timer_init (void){
+	TCCR0B |= (1<<1);		/* Set the clock select bit to pre-scaler 2 
+								1MHz / 8 (pre-scaler 2) ==> 125KHz */
+	
+	TCCR0A |= (1<<1);		/* Set WGM01 to high to enable CTC mode */
+	TIMSK0 |= (1<<1);		/* Set OCIE0A to high to rise an interrupt when the counter matches OCR0A */
+	
+	OCR0A = 125;			/* Set the Output Compare Register 0 A to 125 to trigger interrupt every 1ms
+								1MHz / 8 (pre-scaler 2) / 125 ==> 1KHz (1ms) */
+}
+
+	
+uint16_t 
+Timer_getTick(void){
+	return cntr;
+}
+
+
+ISR(TIMER0_COMPA_vect){
+	cntr++;
+}
+
+/*
+ISR(TIMER0_OVF_vect){
+	cntr++;
+}
+//*/
\ No newline at end of file
diff --git a/EmbeddedSystemsTHM/Timer.h b/EmbeddedSystemsTHM/Timer.h
new file mode 100644
index 0000000..a70a8bf
--- /dev/null
+++ b/EmbeddedSystemsTHM/Timer.h
@@ -0,0 +1,16 @@
+/*
+ * Timer.h
+ *
+ * Created: 28/10/2021 17:49:26
+ *  Author: n0x
+ */ 
+
+
+#ifndef TIMER_H_
+#define TIMER_H_
+#include <avr/io.h>
+
+void Timer_init(void);
+uint16_t Timer_getTick(void);
+
+#endif /* TIMER_H_ */
\ No newline at end of file
diff --git a/EmbeddedSystemsTHM/main.c b/EmbeddedSystemsTHM/main.c
index 4870e37..3141fa8 100644
--- a/EmbeddedSystemsTHM/main.c
+++ b/EmbeddedSystemsTHM/main.c
@@ -7,34 +7,61 @@
 
 #include "Led.h"
 #include "Taster.h"
+#include "Timer.h"
 #include <util/delay.h>
+#include <avr/interrupt.h>
 #ifdef F_CPU
 #define F_CPU 1000000
 #endif
 
 /* function declarations */
-void task1 ();
+void task1 (void);
+void tast2 (void);
 
 /* global variables */
-int g_counter = 0;
+volatile int g_counter = 0;
+int ledStatus = 0;
 
 /* functions */
 int 
 main (void)
 { 
-	// Initialize the LEDs and Buttons
+	sei();
+	
+	/* Initialize the LEDs and Buttons */
 	Led_init();
 	Taster_init();
+	Timer_init();
+
 	
     while (1) 
     {
-		// Run Task 1 
-		task1();
+		/* Run Task 1 */
+		//task1();
+		
+		/* Run Task 2 */
+		task2();
     }
 }
 
 
-/* Tast 1 (2021-10-21)  */
+/* Task 2 (2021-10-28)  */
+void
+task2 () {
+	
+	if(Timer_getTick() % 1000 == 0){
+		ledStatus++;
+	}
+	
+	if(ledStatus % 2 == 0){
+		Led1_On();
+	} else {
+		Led1_Off();
+	}
+}
+
+
+/* Task 1 (2021-10-21)  */
 void
 task1 () {
 	_delay_ms(50);
@@ -50,16 +77,16 @@ task1 () {
 	* 8 = alle LEDs an.
 	*/
 		
-	// Check if counter needs to be incremented 
+	/* Check if counter needs to be incremented */
 	if (Taster1_get()) g_counter++;
 
-	// Check if counter needs to be decremented
+	/* Check if counter needs to be decremented */
 	if (Taster2_get()) g_counter--;
 
-	// Keep counter within boundaries (0-8)
+	/* Keep counter within boundaries (0-8) */
 	g_counter = (g_counter + 9) % 9;
 		
-	// Set the LEDs according to the counter
+	/* Set the LEDs according to the counter */
 	g_counter >= 1 ? Led1_On() : Led1_Off();
 	g_counter >= 2 ? Led2_On() : Led2_Off();
 	g_counter >= 3 ? Led3_On() : Led3_Off();