I am working on a STM32F0 microcontroller based embedded system which is supposed to identify a distinct sound made by a buzzer. I have an electret mic whose signal is amplified and then fed to the ADC. The sound lasts for around 2-4 seconds. What are some methods/algorithms for identifying such sounds? I am aware of audio fingerprinting but I think it will not be possible to implement it on the embedded system given the limited memory of the microcontroller. Also the type of sounds are simple and not much complex. I have heard about methods like cross correlation and matched filter. But having limited knowledge about DSP I am not aware how to actually use these for sound detection, also should they be applied in time domain or frequency domain. Any sort of guidance/resources will be highly appreciated.