今天调试STM32F030 USART2，收发不了数据，仿真的时候进入不了中断，但是配置也是正确的。搞了很久，原因是先初始化的串口再初始化Flash数据，导致读入的波特率是0，进而无法正常使用USART2，浪费了大量的时间，血的教训呀。

void UartIntial(void){

int i;

GPIO_InitTypeDef   GPIO_uInitStructure;

USART_InitTypeDef  USART_uInitStructure;

NVIC_InitTypeDef NVIC_InitStructure; 

for(i=0; i

memset((unsigned char*)&uart[i], 0x00, sizeof(struct UartApiBuf));

uart[i].Snd.IsSndIng = FALSE;

uart[i].Snd.IsRcvIng = FALSE;

uart[i].Snd.lpChar = 0;

uart[i].Snd.lpIdle = 0;

uart[i].Rcv.IsSndIng = FALSE;

uart[i].Rcv.IsRcvIng = FALSE;

uart[i].Rcv.lpChar = 0;

uart[i].Rcv.lpIdle = 0;

}

// USART2_EN -> PA0 

// USART2_TX -> PA2 

  // USART2_RX -> PA3

RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2,ENABLE);

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA,ENABLE);

RCC_APB1PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);

GPIO_PinAFConfig(GPIOA,GPIO_PinSource2,GPIO_AF_1);

GPIO_PinAFConfig(GPIOA,GPIO_PinSource3,GPIO_AF_1);

GPIO_uInitStructure.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_3;

GPIO_uInitStructure.GPIO_Mode = GPIO_Mode_AF;

GPIO_uInitStructure.GPIO_OType = GPIO_OType_PP;  

GPIO_uInitStructure.GPIO_PuPd = GPIO_PuPd_UP;

GPIO_uInitStructure.GPIO_Speed = GPIO_Speed_50MHz;  // 50M

GPIO_Init(GPIOA,&GPIO_uInitStructure);

GPIO_uInitStructure.GPIO_Pin = GPIO_Pin_0;

GPIO_uInitStructure.GPIO_Mode = GPIO_Mode_OUT;

GPIO_uInitStructure.GPIO_OType = GPIO_OType_PP;  

GPIO_uInitStructure.GPIO_PuPd = GPIO_PuPd_UP;

GPIO_uInitStructure.GPIO_Speed = GPIO_Speed_50MHz;  // 50M

GPIO_Init(GPIOA,&GPIO_uInitStructure);

GPIO_ResetBits(GPIOA, GPIO_Pin_0);

NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;

  NVIC_InitStructure.NVIC_IRQChannelPriority = 0;

  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

  NVIC_Init(&NVIC_InitStructure);

USART_uInitStructure.USART_BaudRate = s.Baud;

USART_uInitStructure.USART_Parity = USART_Parity_No;

USART_uInitStructure.USART_StopBits = USART_StopBits_1;

USART_uInitStructure.USART_WordLength = USART_WordLength_8b;

USART_uInitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;

USART_uInitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;

USART_Init(USART2,&USART_uInitStructure);

USART_ITConfig(USART2,USART_IT_RXNE,ENABLE);

  USART_Cmd(USART2,ENABLE);

}