how I implement fast Fourier transform on stm32f303vc discovery board and if i have to give sine wave as a input for fft calculation how it is possible?

[srana]

my project is based on energy optimization of stm32f303. so for that how i supply different input voltage (because i use dynamic voltage scaling) and i how i measure the current value?

[AvaTar]

Download the F30x DSP Peripheral Library from ST's site, which contains a FFT example.

This example progam uses a constant data array as input. Replace this constant array with your own data, which you get from the ADC.

Said peripheral library also contains ADC examples you can use for a start. They will need some tweaking, because the ADC channel might not match, and the generally used ADC mode (continuous mode) is not appropriate for Fourier analysis.