/**
  **************************************************************************
  * @file     readme.txt 
  * @version  v2.0.0
  * @date     2021-11-26
  * @brief    readme
  **************************************************************************
  */

  this demo is based on the at-start board, in this demo, shows how to build
  a app device use hid class protocol. the app demo toggle at-start board led4.
  for more detailed information. please refer to the application note document
  AN0007.
