/*!
    \file    readme.txt
    \brief   USART synchronous
    
    \version 2021-10-30, V1.0.0, firmware for GD32W51x
*/

/*
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*/

  This example is based on the GD32W515P-EVAL-V1.0 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 are the same, LED1 will be 
on, otherwise off. If the data transmitted from SPI0 and received by USART0 
are the same, LED2 will be on, otherwise off.
 
  connect SPI0 SCK  pin(PA5) TO USART0_CK  pin(PA8)
  connect SPI0 MISO pin(PA6) TO USART0_RX  pin(PA1)
  connect SPI0 MOSI pin(PA7) TO USART0_TX  pin(PA0)
