diff --git a/firmware/cup.c b/firmware/cup.c
index de043dc..dd530b6 100644
--- a/firmware/cup.c
+++ b/firmware/cup.c
@@ -18,7 +18,7 @@ uint8_t setting_timeout = 0;
 
 uint8_t adc_pos = 0;
 uint16_t adc_sum = 0;
-uint16_t temp = 0;
+uint16_t temperature = 0;
 uint16_t target = 0;
 
 uint8_t heat_pwm = 0;
@@ -125,14 +125,16 @@ int main(void)
 			/* new adc result */
 			ADCSRA |= (1 << ADIF);
 			adc_sum += ADC;
-			if(!++adc_pos)
+			if(++adc_pos == 64)
 			{
-				temp = adc_sum;
+				temperature = adc_sum;
+				adc_sum = 0;
+				adc_pos = 0;
 			}
 		}
 		
 		if(setting_timeout) {led_set(target);}
-		else {led_set(temp);}
+		else {led_set(temperature);}
 	}
 	
 	return 0;