Added comments

Geigerzaehler/main.c

@@ -1,16 +1,19 @@
 /*
  * geigerzaehler.main.c.c
  *
- * Created: 28.02.2019 09:07:22
- * Author : John_Ditgens
+ * Created			:	28.02.2019 09:07:22
+ * Author			:	John Ditgens, Alexander Brandscheidt
+ * Git-Repository	:	https://gitea.Railduction.eu/JohnD/Geigerzaehler.git
+ *
+ * MController		:	AtMega328P
+ * Board			:	Arduino Nano
  */ 
-#define F_CPU ...UL 					// Taktfrequenz (...)Hz
+#define F_CPU 20000000UL 					// Clock speed: 20 MHz	- Maximum of AtMega328P
 
+// Imports
 #include <avr/io.h>
 #include <avr/interrupt.h>
 
-// Todo: Clock speed missing
-
 int main(void)
 {
     DDRD &= ~(1<<2); 				// Eingang PD2
@@ -25,8 +28,9 @@ int main(void)
     EICRA |= (1 << ISC11)|(1 << ISC10);
     EIMSK |= (1 <<INT1);
 	
-    sei();
+    sei();		// Activate global interrupts
 	
+	// Endless loop
     while (1) 
     {
     }