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

  this demo is based on the ht32f49163_sk board, in this demo, provides a short
  description of how to use the jtag/swd ios as standard gpios or mux other
  peripheral. the pa13(jtms/swdat) as general io output push-pull toggled, 
  pa14(jtck/swclk) as usart2 tx send data.
