Amateur Radio Hobbyist VE3MKC has been working on a project involving running a SoftRock SDR on a Teensy 3.1 Microcontroller. The Teensy is a tiny microcontroller board that uses a 32-bit ARM processor and the SoftRock SDR is a HF only software defined radio kit.
VE3MKC wrote code to first digitize then multiply the signal with a digital VFO before finally applying a low pass filter. He found that the Teensy’s microcontroller has sufficient CPU power to have an LCD RF spectrum display and process the audio output at the same time. Two videos of his project have been uploaded to YouTube.