stm32标准库串口怎么发送字符数据

在使用STM32标准库的串口发送字符数据，需要进行以下步骤：

1. 初始化串口

    USART_InitTypeDef USART_InitStructure;
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
    USART_InitStructure.USART_BaudRate = 9600;
    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);

2. 发送字符

    while(USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET);
    USART_SendData(USART1, ch);

其中，`USART_GetFlagStatus(USART1, USART_FLAG_TC)`用于检查发送完成标志。

完整代码示例：

#include "stm32f10x.h"

int main(void)
{
    char ch = 'A';

    USART_InitTypeDef USART_InitStructure;
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
    USART_InitStructure.USART_BaudRate = 9600;
    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);

    while (1) {
        while(USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET);
        USART_SendData(USART1, ch);
    }
}