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

    \version 2017-02-10, V1.0.0, firmware for GD32F30x
    \version 2018-10-10, V1.1.0, firmware for GD32F30x
    \version 2018-12-25, V2.0.0, firmware for GD32F30x
    \version 2020-09-30, V2.1.0, firmware for GD32F30x
*/

/*
    Copyright (c) 2020, GigaDevice Semiconductor Inc.

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are permitted provided that the following conditions are met:

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       may be used to endorse or promote products derived from this software without 
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*/

  This demo is based on the GD32307C-EVAL-V1.1, 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, LED2 and
LED4 will be on, otherwise off. If the data transmitted from SPI0 and 
received by USART0 are 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)