STMicroelectronics is known for its Discovery family boards – quite cheap but very functional development tools. One of them is STM32F746G-DISCO (32F746GDISCOVERY) with a large LCD-TFT, Ethernet, audio line in and out jacks and some other features. Using these features I decided to build a simple scope which allows to sample the signal from audio in line and display it together with its FFT spectrum.
The project was created using SW4STM32 – a free, eclipse based IDE for STM32 microcontrollers running on both, Linux and Windows platforms. For simpler application development, the FreeRTOS was added to the project, together with STemWin graphical library for GUI and CMSIS DSP mathematical and signal processing library for FFT computation. All mentioned software can be downloaded from SW4STM32 during new project creation.
The source code of this project is available on my public github repository:
And here you can see how it works: