limit spooling speed

spule.c

@@ -33,7 +33,6 @@ void timer5_init()
     OCR5C = 500;
 
     DDRL |= 1 << 5;
-
 }
 
 void do_spule(){
@@ -58,6 +57,10 @@ void do_spule(){
     else{
         /* speed regulation - keep taenzer at 10% */
         int32_t tmp = (100 - (int32_t)taenzer_state.pos/1000)*10;
+
+        if(tmp < -75000/abzug_speed/2)
+            tmp = -75000/abzug_speed/2;
+
         ICR5=75000/abzug_speed + tmp;
         OCR5C = ICR5/2;