diff --git a/include/adc.c b/include/adc.c
index 0bba25d..dfba26d 100644
--- a/include/adc.c
+++ b/include/adc.c
@@ -5,13 +5,13 @@
 #include <util/delay.h>
 
 void adc_init() {
-	DDRC=0x0; // does not exist but is default?
-	ADCSRA = (1<<ADEN)|(1<<ADPS1)|(1<<ADPS2);
-	ADMUX = (1<<REFS0);
+	DDRC=0x0; // read from port c
+	ADCSRA = (1<<ADEN)|(1<<ADPS1)|(1<<ADPS2); // magic enable adc
+	ADMUX = (1<<REFS0); // magic enable multiplexer
 }
 uint16_t adc_read(uint8_t channel) {
     ADMUX &= 0xf0; // max channel?
-    ADMUX |= (channel & 0x0f); // select channel
+    ADMUX |= (channel & 0x0f); // select channel, max 2^4?
     ADCSRA |= (1<<ADSC); // interrupt enable
     while((ADCSRA&(1<<ADIF))==0); // wait for something
     return ADCL + (ADCH << 8); // read