This is a genius bit of 'bored at home' hacking. Some other links to similar projects. https://www.instructables.com/id/Secret-Knock-Detecting-Door-Lock/ http

This is a genius bit of 'bored at home' hacking. Some other links to similar projects. https://www.instructables.com/id/Secret-Knock-Detecting-Door-Lock/ https://www.instructables.com/id/Secret-Knock-Detecting-Door... https://hackaday.com/2020/05/25/secret-knock-unlocks-door/ https://hackaday.com/2020/05/25/secret-knock-unlocks-door/