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

  this demo is based on the at-start board, in this demo, swith sclk to
  pll based hick when hext clock failure occured. pa8 output crm_clkout_pll div 4
  and led2 fresh per 200 ms.for more detailed information. please refer to the 
  application note document AN0084.
