/*!
    \file    readme.txt
    \brief   description of the RS485_Test demo

    \version 2025-01-17, V2.5.0, demo for GD32F3x0
*/

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*/

  This demo is based on the GD32350R-EVAL-V1.0 board, it shows how to use the USART RS485.
In this demo, the same program is loaded to two GD32350R-EVAL boards, then they are 
communicated through connecting respective RS485 line A and B. 
  After system start-up, all the LEDs are turned on and off for test. Some information
is printed in the hyperterminal. When press the buttons(Wakeup or Tamper) on one board,
GD32F350R_EVAL is set as RS485 transmitter or receiver and LED2 is on or LED3 is on. Enable
RS485 receiver first and then enable RS485 transmitter. The RS485 transmitter prints out
the data been transimitted and RS485 receiver prints out the data received in hyperterminal.
If User key is pressed, LED4 is on and hyperterminal displays that set transmit or receive
mode.

  JP12 to RS485
  JP13 to USART
  Connect respective RS485 line A and B
