/**
  **************************************************************************
  * @file     readme.txt 
  * @version  v2.0.5
  * @date     2022-05-20
  * @brief    readme
  **************************************************************************
  */

  this demo is based on the at-start board and at32-comm-ev, in this demo, 
  shows how to use the can communication mode. every 1s transmit one message
  and the led4 blink, if receive a message, led2 blink(message id is 0x400) or led3
  blink(message id is not equal to 0x400).
  set-up
  - can tx      --->   pb9
  - can rx      --->   pb8

  for more detailed information. please refer to the application note document AN0095.

