/**
  **************************************************************************
  * @file     readme.txt
  * @brief    readme
  **************************************************************************
  */

    this demo is based on the at-start board, in this demo, pa8 input
  external signal,debug view to see frequency and dutycycle or use uasrt1 to
  see frequency and dutycycle(pa9:usart1_tx).

  for more detailed information. please refer to the application note document AN0085.

