diff --git a/timer.c b/timer.c
index 6e15ef6..1ba5e7b 100644
--- a/timer.c
+++ b/timer.c
@@ -39,16 +39,19 @@ void timer_init(void)
   timer_time = 0;
   
   // - Time accuracy: 1 millisecond (corresponding frequency: 1kHz)
-  // ==> F_CPU = 2Mhz
-  // ==> 16Mhz / 64 = 250 kHz
-  // ==> let timer count to 250 to get 1kHz frequency
+  // ==> F_CPU = 20Mhz
+  // ==> 20Mhz / 256 = 78.125 kHz
+  // ==> let timer count to 78 to get (almost) 1kHz frequency
   // therefore:
-  // - Set Timer/Counter0 prescaler to 64 ==> (1<<CS01)|(1<<CS00)
-  // - Set OCR2 to 249
+  // - Set Timer/Counter0 prescaler to 256 ==> (1<<CS02)
+  // - Set OCR2 to 78
   // - CTC ( i.e. clear counter, when COUNTER == OCR0A) ==> (1<<WGM01)
-  OCR0A = 249;
+  // unfortunately, due to the 20MHz and the coarse prescaler dividers
+  // provided, we can't get any closer to the desired frequency of
+  // 1kHz :(
+  OCR0A = 78;
   TCCR0B = (1<<WGM02);
-  TCCR0A = (1<<CS01)|(1<<CS00);  
+  TCCR0A = (1<<CS02);
 
   // Interrupts setzen
   TIMSK0 |= (1<<OCIE0A);