ESP8266-based Siren activated by Passive Infrared Sensor The program creates a WiFi access point, "SirenAccessPoint". and you log into it using your smartphone. You then type into your favorite browser:
http://192.168.4.1/arm to turn the alarm on
http://192.168.4.1/disable to turn the alarm off
http://192.168.4.1/sirenon to turn the siren on
http://192.168.4.1/sirenoff to turn the siren off
https://cmheong.blogspot.com/2020/03/iot-home-alarm-new-beginning.html