diff --git a/firmware/Makefile.inc b/firmware/Makefile.inc
index 56c4ba1..720d460 100644
--- a/firmware/Makefile.inc
+++ b/firmware/Makefile.inc
@@ -2,7 +2,8 @@ CFLAGS += -save-temps
 CFLAGS += -std=gnu99 -Wall # implements C99, for <util/atomic.h>
 # this removes dead code and does global linker optimization
 #CFLAGS += -ffunction-sections -Wl,--gc-sections -Wl,--relax 
-CFLAGS += -Wall -Os  -I. -mmcu=atmega88 -lm -ffunction-sections -fdata-sections -Wl,--relax -ffreestanding
+CFLAGS += -Wall -Os  -I. -mmcu=atmega88 -lm -ffunction-sections -fdata-sections  -Wl,--relax 
+# -ffreestanding # -ffreestanding breaks compile-time eval, which is used to precompute some values (like in _delay_us)
 
 # further optimization:
 #CFLAGS += --param inline-call-cost=2 
diff --git a/firmware/shared/softtimer.h b/firmware/shared/softtimer.h
index 936eb26..fc57812 100644
--- a/firmware/shared/softtimer.h
+++ b/firmware/shared/softtimer.h
@@ -21,5 +21,7 @@ uint8_t softtimer(uint8_t timernum, uint16_t interval);
 // SOFTTIMER( <YOUR TIMER NUM>, <YOUR INTERVAL>);
 #define SOFTTIMER(n,a) if(softtimer((n),(a*4)))
 
+//TODO: use a static uint16 in the #define to store softtimer_last, and pass
+//it by reference to softtimer(). That way SOFTTIMERNUMS is unnecessary
 
 #endif
diff --git a/firmware/slavechip/main.c b/firmware/slavechip/main.c
index f0fe4da..b5106ff 100644
--- a/firmware/slavechip/main.c
+++ b/firmware/slavechip/main.c
@@ -42,7 +42,7 @@ int32_t avg_temp(int16_t val, uint8_t channel) {
 
 uint16_t calc_temp(int16_t val, uint8_t channel) {
 	float mV =  ((float) avg_temp(val, channel))/1000000;
-	uint16_t temp;
+	uint16_t temp = 0;
 	if(mV < 0) {
 		/* t in mV
 		E = sum(i=0 to n) c_i t^i.		; n=10
@@ -61,9 +61,8 @@ uint16_t calc_temp(int16_t val, uint8_t channel) {
 			-0.163226974860E-22
 		};
 		for(int i=0; i<11; i++) {
-			temp += coef[i] * pow(mV, i+1);
+			temp += coef[i] * pow(mV, i);
 		}
-		return temp;
 	} else {
 		/*
 		  t in mV
@@ -83,10 +82,13 @@ uint16_t calc_temp(int16_t val, uint8_t channel) {
 		};
 		float a[] = {0.118597600000E+00, -0.118343200000E-03, 0.126968600000E+03};
 		for(int i=0; i<10; i++) {
-			temp += coef[i]*pow(mV, i+1) + a[0] * pow(exp(a[1]*(mV - a[2])), 2);
+			temp += coef[i]*pow(mV, i) 
 		}
+		// ich glaube das summenzeichen erstreckt sich nicht auf das exp
+		temp += a[0] * pow(exp(a[1]*(mV - a[2])), 2);
 		
 	}
+	return temp;
 }
 
 /* initializes the hardware */