stm32f103c8t6基于正电原子标准例程-V3.5库函数的UsartPrintf

以下是基于正点原子标准例程V3.5库函数的UsartPrintf代码：

首先，在main.c文件中添加以下代码：

#include "stdio.h"
#include "stdarg.h"
#include "string.h"
#include "stm32f10x_usart.h"
#include "usart.h"

#define USARTx  USART1
#define USARTx_IRQn USART1_IRQn

void USART1_IRQHandler(void)
{
    if(USART_GetITStatus(USARTx, USART_IT_RXNE) != RESET)
    {
        USART_ClearITPendingBit(USARTx, USART_IT_RXNE);
    }
}

int fputc(int ch, FILE *f)
{
    USART_SendData(USARTx, (uint8_t)ch);
    while(USART_GetFlagStatus(USARTx, USART_FLAG_TXE) == RESET);
    return ch;
}

然后，在usart.c文件中添加以下代码：

#include "usart.h"

void USART_Configuration(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    USART_InitTypeDef USART_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    USART_InitStructure.USART_BaudRate = 115200;
    USART_InitStructure.USART_WordLength = USART_WordLength_8b;
    USART_InitStructure.USART_StopBits = USART_StopBits_1;
    USART_InitStructure.USART_Parity = USART_Parity_No;
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
    USART_Init(USART1, &USART_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = USARTx_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    USART_Cmd(USART1, ENABLE);
    USART_ITConfig(USARTx, USART_IT_RXNE, ENABLE);
}

最后，在usart.h文件中添加以下代码：

#ifndef __USART_H
#define __USART_H

#include "stm32f10x.h"

void USART_Configuration(void);

#endif

这样，你就可以在程序中使用printf函数进行串口输出了。例如：

#include "stdio.h"

int main()
{
    USART_Configuration();
    printf("Hello, world!\n");
    while(1);
}