STM32 的 USART 使能USART_IT_RXNE进不了中断，USART_IT_TXE就能进
void USART_Configure()
{
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE );
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 |GPIO_Pin_10;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_USART1);
GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_USART1);
USART_InitStructure.USART_BaudRate = 115200;
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStructure.USART_Mode = USART_Mode_Rx |USART_Mode_Tx;
USART_InitStructure.USART_Parity = USART_Parity_No;
USART_InitStructure.USART_StopBits = USART_StopBits_1;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;
USART_Init(USART1,&USART_InitStructure);
USART_Cmd(USART1,ENABLE);
USART_ClearFlag(USART1,USART_FLAG_RXNE);
USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);//USART_IT_TXE
/* 中断*/
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//优先级分布
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;
NVIC_Init(&NVIC_InitStructure);
}
void USART1_IRQHandler(void)
{
u8 res;
if(USART_GetITStatus(USART1,USART_IT_RXNE)==SET)
{
USART_ClearFlag(USART1,USART_FLAG_RXNE);
USART_ClearITPendingBit(USART1,USART_IT_RXNE);
res = USART_ReceiveData(USART1);
USART_SendData(USART1,res);
}
while (1)
{
USART_SendData(USART1,'C');
while(RESET == USART_GetFlagStatus(USART1,USART_FLAG_TXE));
}
}
//
int main(void)
{
SystemInit();
USART_Configure();
delay(1000);
while (1)
{
USART_SendData(USART1,'a');
while(RESET == USART_GetFlagStatus(USART1,USART_FLAG_TXE));
delay(1000);
}
}
