GD32VF103的串口发送问题（已解决）

/*!

    \file  main.c

    \brief running led demo



    \version 2019-06-05, V1.0.0, demo for GD32VF103

*/



/*

    Copyright (c) 2019, GigaDevice Semiconductor Inc.



    Redistribution and use in source and binary forms, with or without modification,

are permitted provided that the following conditions are met:



    1. Redistributions of source code must retain the above copyright notice, this

       list of conditions and the following disclaimer.

    2. Redistributions in binary form must reproduce the above copyright notice,

       this list of conditions and the following disclaimer in the documentation

       and/or other materials provided with the distribution.

    3. Neither the name of the copyright holder nor the names of its contributors

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

       specific prior written permission.



    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.

IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,

INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,

WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY

OF SUCH DAMAGE.

*/

#include <stdio.h>

#include "gd32vf103.h"

#include "gd32vf103c_start.h"

#include "systick.h"



void usart0_config(void);

/*!

    \brief      main function

    \param[in]  none

    \param[out] none

    \retval     none

*/

int main(void)

{  

        usart0_config();

    /* enable the LED clock */

    rcu_periph_clock_enable(RCU_GPIOA);

    /* configure LED GPIO port */

    gpio_init(GPIOA, GPIO_MODE_OUT_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_7);



    gpio_bit_reset(GPIOA, GPIO_PIN_7);



    while(1){

        /* insert 500 ms delay */

        delay_1ms(500);



        /* toggle the LED */ 

        gpio_bit_write(GPIOA, GPIO_PIN_7, (bit_status)(1-gpio_input_bit_get(GPIOA, GPIO_PIN_7)));

        

        /* insert 500 ms delay */

        delay_1ms(500);

        printf("123\r\n");

    }

}



/*!

\brief      USART0 configure

\param[in]  none

\param[out] none

\retval     none

*/

void usart0_config(void)

{

        /* enable USART clock */

        rcu_periph_clock_enable(RCU_USART0);

        #if defined USART0_REMAP

        /* enable GPIO clock */

        rcu_periph_clock_enable(RCU_GPIOB);

        rcu_periph_clock_enable(RCU_AF);

        /* USART0 remapping */

        gpio_pin_remap_config(GPIO_USART0_REMAP, ENABLE);

        /* connect port to USARTx_Tx */

        gpio_init(GPIOB, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_6);

        /* connect port to USARTx_Rx */

        gpio_init(GPIOB, GPIO_MODE_IN_FLOATING, GPIO_OSPEED_50MHZ, GPIO_PIN_7);

        #else

        /* enable GPIO clock */

        rcu_periph_clock_enable(RCU_GPIOA);



        /* connect port to USARTx_Tx */

        gpio_init(GPIOA, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_9);

        /* connect port to USARTx_Rx */

        gpio_init(GPIOA, GPIO_MODE_IN_FLOATING, GPIO_OSPEED_50MHZ, GPIO_PIN_10);

        #endif



        /* USART configure */

        usart_deinit(USART0);

        usart_baudrate_set(USART0, 115200U);

        usart_word_length_set(USART0, USART_WL_8BIT);

        usart_stop_bit_set(USART0, USART_STB_1BIT);

        usart_parity_config(USART0, USART_PM_NONE);

        usart_hardware_flow_rts_config(USART0, USART_RTS_DISABLE);

        usart_hardware_flow_cts_config(USART0, USART_CTS_DISABLE);

        usart_receive_config(USART0, USART_RECEIVE_ENABLE);

        usart_transmit_config(USART0, USART_TRANSMIT_ENABLE);

        usart_enable(USART0);

}



/* retarget the C library printf function to the USART */

int _put_char(int ch)

{

usart_data_transmit(USART0, (uint8_t) ch );

while ( usart_flag_get(USART0, USART_FLAG_TBE)== RESET){

}



return ch;

}