#include <DHT.h>
DHT sensor1(PA0, DHT22);
DHT sensor2(PA1, DHT22);

void change_sensor();
void alarm();
int geschw = 0;

bool read_from = true;

void setup() {
  Serial.begin(115200);
  pinMode(PA4, INPUT);
  pinMode(PA2, OUTPUT);
  attachInterrupt(digitalPinToInterrupt(PA4), change_sensor, FALLING);
}

void change_sensor() {
  read_from =! read_from;
  Serial.println("Sensorwechsel!");
}

void alarm() {

  if (sensor1.readHumidity() > 50) {
    geschw = 500;
  } if (sensor1.readTemperature() > 30) {
    geschw = 100;
  } else {
    geschw = 0;
    digitalWrite(PA2, LOW);
  }
  blinken(geschw);
}

void blinken(int i) {
  while (i > 0) {
    delay(i);
    digitalWrite(PA2, !digitalRead(PA2));
    Serial.println("ALARM!");
  }
}

void loop() {
  delay(1000);
  if (read_from) {
    Serial.println("Temp: " + String(sensor1.readTemperature(), 2) + "°C");
  } else {
    Serial.println("Humidity: " + String(sensor1.readHumidity(), 1) + "%");
  }
  
  Serial.println("---");
 
}