写一段stm32串口打印字符串的程序

您好，以下是一段基于STM32的串口打印字符串的程序：

#include "stm32f10x.h"
#include "stdio.h"

void USART1_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | 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_Tx;
USART_Init(USART1, &USART_InitStructure);

USART_Cmd(USART1, ENABLE);
}

void USART1_SendChar(char ch)
{
while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
USART_SendData(USART1, (uint16_t)ch);
}

void USART1_SendString(char* str)
{
while (*str)
{
USART1_SendChar(*str++);
}
}

int main(void)
{
USART1_Init();

char* str = "Hello, world!";
USART1_SendString(str);

while (1);

return ;
}