/*!
    \file    readme.txt
    \brief   USART synchronous

    \version 2025-07-15, V1.0.0, firmware for GD32G5x3
*/

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*/

  This example is based on the GD32G553Q-EVAL-V1.0 board, it provides a basic
communication between USART1 (Synchronous mode) and SPI0. First, USART1
transmits a series of data to SPI0, then SPI0 transmits a series of data
to USART1. Compare the transmitted data and the received data. If the
data transmitted from USART1 and received by SPI0 are the same, LED1 will be
on, otherwise off. If the data transmitted from SPI0 and received by USART1
are the same, LED2 will be on, otherwise off.

  connect SPI0 SCK  pin(PB3) TO USART1_CK pin(PA4)
  connect SPI0 MISO pin(PB4) TO USART1_RX pin(PA3)
  connect SPI0 MOSI pin(PB5) TO USART1_TX pin(PA2)
