A crystal oscillator pulses a relatively large electromagnet. ... Fun fact: atmega chips contained in many of Arduino models have an operating mode specifically for clock-type devices.

30 thoughts on “ Remove Your Arduino’s External Oscillator To Gain A Free Pair Of IO Pins ” Felicitus says: ... But crystal != oscillator. It’s only a part of it that defines frequency.

Starting a crystal oscillator fast in an IoT node is an art: the high Q needed for stability means they take milliseconds to get going, just to transmit a 128μs Bluetooth LE packet, and power is at a ...