void test_function() {
  static bool send_fl, send_danger;
  static unsigned long send_pause, send_pause_danger;
  /* #Check Temperature Level */
  /* 24 - Warn / 30 - DANGER */
  if(temp1 == 24 || temp2 == 24 || temp3 == 24 || temp4 == 24) {
    // Send warn msg
    if(!send_fl) {
     if(temp1 == 24) {
       sendSMS("+79029288910", "WARNING! SENSOR #1 24℃");
       sendSMS("+79538533436", "WARNING! SENSOR #1 24℃");
       send_pause = millis();
       send_fl = true;
     } else if(temp2 == 24) {
       sendSMS("+79029288910", "WARNING! SENSOR #2 24℃");
       sendSMS("+79538533436", "WARNING! SENSOR #2 24℃");
       send_pause = millis();
       send_fl = true;
     } else if(temp3 == 24) {
       sendSMS("+79029288910", "WARNING! SENSOR #3 24℃");
       sendSMS("+79538533436", "WARNING! SENSOR #3 24℃");
       send_pause = millis();
       send_fl = true;
     } else if(temp4 == 24) {
       sendSMS("+79029288910", "WARNING! SENSOR #4 24℃");
       sendSMS("+79538533436", "WARNING! SENSOR #4 24℃");
       send_pause = millis();
       send_fl = true;
     }
   }
   if(send_fl) {
     if((millis() - send_pause) >= 900000) { // 15min pause
       send_fl = false;
     }
   }

  }
  if(temp1 >= 30 || temp2 >= 30 || temp3 >= 30 || temp4 >= 30) {
    // send danger msg
    if(!send_danger) {
      if(temp1 >= 30) {
        sendSMS("+79029288910", "DANGER! SENSOR #1 >29℃");
        sendSMS("+79538533436", "DANGER! SENSOR #1 >29℃");
        send_pause_danger = millis();
        send_danger = true;
      } else if(temp2 >= 30) {
        sendSMS("+79029288910", "DANGER! SENSOR #2 >29℃");
        sendSMS("+79538533436", "DANGER! SENSOR #2 >29℃");
        send_pause_danger = millis();
        send_danger = true;
      } else if(temp3 >= 30) {
        sendSMS("+79029288910", "DANGER! SENSOR #3 >29℃");
        sendSMS("+79538533436", "DANGER! SENSOR #3 >29℃");
        send_pause_danger = millis();
        send_danger = true;
      } else if(temp4 >= 30) {
        sendSMS("+79029288910", "DANGER! SENSOR #4 >29℃");
        sendSMS("+79538533436", "DANGER! SENSOR #4 >29℃");
        send_pause_danger = millis();
        send_danger = true;
      }
    }
    if(send_danger) {
      if(millis() - send_pause_danger) >= 300000) {
        send_danger = false;
      }
    }
  }
  /* #Read "Test" Message */
}
/* TEST FUNCTION */