This project is microphone based and require minimal external components. 2 x LR44 coin cells are used so that I can have the whole structure working in the confines of a 170 tie-point mini breadboard. ADC10, TimerA interrupt LPM wake-up, TimerA PWM like output, button use, integer arithmetic are used and demonstrated.
Features
8 bit integer FFT 16 samples at 500Hz separationshows 8 amplitudes of 1K, 1.5K, 2K, 3K, 4K, 5K, 6K, 7.5K non-linearpartial logarithm map to show amplitudes, limited as resolution has been reduced for 8 bit FFTTLC272 one stage mic amplifys at 100x times 100x gain (you can experience w/ 2 stages)menu selectable optional Hamming windowmenu adjust 4 levels brightnessmenu adjust 8 levels sample rate / response time2 x LR44 coin cell powered “on board”“

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