Hello, I am new to electronics and I would like to make a power outage alarm with a Raspberry Pi Pico 2 circuit that I bought as a kit. The Pico would be connected via USB and when a power outage occurs, a two-hour timer would start and after these two hours an alarm would sound. The circuit would be powered by a 9 volt battery for two hours. The alarm could sound for one minute with a bib every two seconds. If the power comes back on before two hours, I would like the timer to reset. Do you have any solutions to suggest or examples of circuits adaptable to this project? Thank you very much for your help.
