STM32F407FFT

代码说明：

  使用STM32官方提供的DSP库进行FFT，虽然在使用上有些不灵活（因为它是基4的FFT，所以FFT的点数必须是4^n），但其执行效率确实非常高效，看图1所示的FFT运算效率测试数据便可见一斑。该数据来自STM32 DSP库使用文档(. Using the official DSP library provided by STM32 for FFT is not flexible in use (because it is the FFT of base 4, so the number of FFT points must be 4 ^ n), but its execution efficiency is really very efficient, as can be seen from the test data of FFT operation efficiency shown in Figure 1. This data comes from STM32 DSP library usage document)