This is another very simple project and kind of geeky. I’ve made my own digital watch. If you think there is nothing to learn with this simple project, well, you’re wrong. We will learn how to use the ATmega328p - AU chip without an external clock by burning an 8MHz internal clock bootloader. The chip will work at low voltage, 3.2 volts from a button cell battery. The battery has low capacity, so, we need a low consumption.”

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