 
 void calcSignal4() {
   last_interrupt_time4 = micros();
-  if (digitalRead(A4) == HIGH) {
+  if (digitalRead(A3) == HIGH) {
     chrono_start4 = micros();
   }
   else {


void calcSignal3() {
  last_interrupt_time3 = micros();
  if (digitalRead(A3) == HIGH) {
    chrono_start3 = micros();
  }
  else {


void calcSignal2() {
  last_interrupt_time2 = micros();
  if (digitalRead(A1) == HIGH) {
    chrono_start2 = micros();
  }
  else {
