+ Serial.print(time);
+ Serial.print(",");
+ Serial.print(co2);
+ Serial.print(",");
+ Serial.println(temp);
+
+ digitalWrite(led_red_pin, co2 >= co2_alarm_thr);
+ digitalWrite(led_yellow_pin, co2 >= co2_warning_thr && co2 < co2_alarm_thr);
+ digitalWrite(led_green_pin, co2 < co2_warning_thr);
+
+ if (co2 >= co2_alarm_thr && lastppm < co2_alarm_thr) {
+ digitalWrite(buzzer_pin, HIGH);
+ delay(100);
+ digitalWrite(buzzer_pin, LOW);
+ delay(100);
+ digitalWrite(buzzer_pin, HIGH);
+ delay(100);
+ digitalWrite(buzzer_pin, LOW);
+ delay(100);
+ digitalWrite(buzzer_pin, HIGH);
+ delay(100);
+ digitalWrite(buzzer_pin, LOW);
+ }
+
+ if (co2 >= co2_warning_thr && lastppm < co2_warning_thr) {
+ digitalWrite(buzzer_pin, HIGH);
+ delay(500);
+ digitalWrite(buzzer_pin, LOW);
+ }
+
+ lcd.setCursor(0, 0);
+ lcd.print("CO2: ");
+ lcd.print(co2);
+ lcd.print(" ppm ");
+ lcd.setCursor(0, 1);
+ lcd.print("Temp: ");
+ lcd.print(temp);
+ lcd.print(" C +/- ");
+
+ lastppm = co2;
+ delay(5000);
+}