l 串口时钟使能，GPIO时钟使能:
RCC_APB2PeriphClockCmd();
l 串口复位:
USART_DeInit(); 这一步不是必须的
l GPIO端口模式设置:
GPIO_Init();
l 串口参数初始化：
USART_Init();
l 开启中断并且初始化NVIC（如果需要开启中断才需要这个步骤）
NVIC_Init();
USART_ITConfig();
l 使能串口:
USART_Cmd();
l 编写中断处理函数：
USARTx_IRQHandler();
l 串口数据收发：
void USART_SendData();//发送数据到串口，DR
uint16_t USART_ReceiveData();//接受数据，从DR读取接受到的数据
l 串口传输状态获取：
FlagStatus USART_GetFlagStatus(USART_TypeDef* USARTx, uint16_t USART_FLAG);
void USART_ClearITPendingBit(USART_TypeDef* USARTx, uint16_t USART_IT);
l 源代码：
#pragma import(__use_no_semihosting)
struct __FILE
{
int handle;
}; FILE __stdout;
void _sys_exit(int x)
{
x = x;
}
int fputc(int ch, FILE *f)
{
while((USART1->SR&0X40)==);
USART1->DR = (u8) ch;
return ch;
} void uart_init(u32 bound){
//GPIO¶Ë¿ÚÉèÖÃ
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure; RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1|RCC_APB2Periph_GPIOA, ENABLE); //ʹÄÜUSART1£¬GPIOAʱÖÓ //USART1_TX GPIOA.9
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; //PA.9
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //¸´ÓÃÍÆÍìÊä³ö
GPIO_Init(GPIOA, &GPIO_InitStructure);//³õʼ»¯GPIOA.9 //USART1_RX GPIOA.10³õʼ»¯
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;//PA10
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;//¸¡¿ÕÊäÈë
GPIO_Init(GPIOA, &GPIO_InitStructure);//³õʼ»¯GPIOA.10 //Usart1 NVIC ÅäÖÃ
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority= ;//ÇÀÕ¼ÓÅÏȼ¶3
NVIC_InitStructure.NVIC_IRQChannelSubPriority = ; //×ÓÓÅÏȼ¶3
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQͨµÀʹÄÜ
NVIC_Init(&NVIC_InitStructure); //¸ù¾ÝÖ¸¶¨µÄ²ÎÊý³õʼ»¯VIC¼Ä´æÆ÷ //USART ³õʼ»¯ÉèÖÃ
USART_InitStructure.USART_BaudRate = bound;//´®¿Ú²¨ÌØÂÊ
USART_InitStructure.USART_WordLength = USART_WordLength_8b;//×Ö³¤Îª8λÊý¾Ý¸ñʽ
USART_InitStructure.USART_StopBits = USART_StopBits_1;//Ò»¸öֹͣλ
USART_InitStructure.USART_Parity = USART_Parity_No;//ÎÞÆæżУÑéλ
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//ÎÞÓ²¼þÊý¾ÝÁ÷¿ØÖÆ
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //ÊÕ·¢Ä£Ê½ USART_Init(USART1, &USART_InitStructure); //³õʼ»¯´®¿Ú1
USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);//¿ªÆô´®¿Ú½ÓÊÜÖжÏ
USART_Cmd(USART1, ENABLE); //ʹÄÜ´®¿Ú1 } void USART1_IRQHandler(void) //´®¿Ú1ÖжϷþÎñ³ÌÐò
{
u8 Res;
if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET) //½ÓÊÕÖжÏ(½ÓÊÕµ½µÄÊý¾Ý±ØÐëÊÇ0x0d 0x0a½áβ)
{
Res =USART_ReceiveData(USART1); //¶ÁÈ¡½ÓÊÕµ½µÄÊý¾Ý if((USART_RX_STA&0x8000)==)//½ÓÊÕδÍê³É
{
if(USART_RX_STA&0x4000)//½ÓÊÕµ½ÁË0x0d
{
if(Res!=0x0a)USART_RX_STA=;//½ÓÊÕ´íÎó,ÖØпªÊ¼
else USART_RX_STA|=0x8000; //½ÓÊÕÍê³ÉÁË
}
else //»¹Ã»ÊÕµ½0X0D
{
if(Res==0x0d)USART_RX_STA|=0x4000;
else
{
USART_RX_BUF[USART_RX_STA&0X3FFF]=Res ;
USART_RX_STA++;
if(USART_RX_STA>(USART_REC_LEN-))USART_RX_STA=;//½ÓÊÕÊý¾Ý´íÎó,ÖØпªÊ¼½ÓÊÕ
}
}
}
}