/*!
    \file    readme.txt
    \brief   USART synchronous
    
    \version 2025-07-31, V3.0.2, firmware for GD32F403
*/

/*
    Copyright (c) 2025, GigaDevice Semiconductor Inc.

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*/

  This demo is based on the GD32403Z-EVAL-V1.1 board, it provides a basic communication 
between USART0 (Synchronous mode) and SPI0. First, USART0 transmits a series of data to 
SPI0, then SPI0 transmits a series of data to USART0. Compare the transmitted data and 
the received data. If the data transmitted from USART0 and received by SPI0 is the same, 
LED2 andLED4 will be on, otherwise off. If the data transmitted from SPI0 and received
by USART0 is the same, LED3 and LED5 will be on, otherwise off.

  connect SPI0 SCK  pin(PA5) TO USART0_CK  pin(PA8)
  connect SPI0 MISO pin(PA6) TO USART0_RX  pin(PA10)
  connect SPI0 MOSI pin(PA7) TO USART0_TX  pin(PA9)

