Kitchen timer

beginner, and totally lost ... I want to realize a timer that would use a fuel gauge, in 12volts, to time a time of 1 hour. On power up, the gauge needle would go to the max, (tank full), and as the minutes pass, every 5 minutes, the needle redescent to the mini, until one hour has elapsed, the gauge indicating zero, (empty tank). I have nothing else to measure or count ... only a delay that elapses and a voltage of 12 volts that drops 12v divided by 12 (5minutes x 12 = 1hour). The perfection, would be that at the last stage, a diode lights up like a reserve alert, to indicate that it remains only 5 minutes before total extinction.

If a charitable and gifted soul could help me with the code, I'd be proud to put all the photos and sketches on line to help my neighbor ...


What “gauge needle” are you referring to? I cannot see one.

Please read: How to use this forum and think about what you’re asking. No one can see what is in your mind, you need to start at the beginning and describe what you want to build. Start with the hardware, the software comes later.

12V is a bit problematic, requires special circuitry. But as Fred asked, what's the electrical characteristic of your gauge? Many such instruments work on current, of a lower voltage. If a voltage higher than 5V is required, a transistor must switch that high voltage.