串口2初始化后一直会输出00 00 00这样的字符

袁小远 · 发表于 2016-6-27 16:40:50

按照串口1的教程初始化了串口2，串口2发送数据，电脑的串口调试助手在十六进制显示时会一直显示有00 00 00 00 00 从串口2发出，查找了很久一直没有找到原因，求大家帮忙看看
void My_USART2_Init(void)
{
GPIO_InitTypeDef  GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2,ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD,ENABLE);
USART_DeInit(USART2);

GPIO_PinAFConfig(GPIOD,GPIO_PinSource5,GPIO_AF_USART2);
GPIO_PinAFConfig(GPIOD,GPIO_PinSource6,GPIO_AF_USART2);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOD, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOD, &GPIO_InitStructure);

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(USART2,&USART_InitStructure);

USART_Cmd(USART2 ,ENABLE);

USART_ITConfig(USART2,USART_IT_RXNE,ENABLE);

NVIC_InitStructure.NVIC_IRQChannel=USART2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1;
NVIC_InitStructure.NVIC_IRQChannelSubPriority=1;
NVIC_Init(&NVIC_InitStructure);
}

void USART2_IRQHandler(void)
{
u8 res;
if(USART_GetITStatus(USART2,USART_IT_RXNE)){

res=USART_ReceiveData(USART2);
USART_SendData(USART2,res);
}

}

/*****************  发送一个字符 **********************/
static void Usart_SendByte( USART_TypeDef * pUSARTx, uint8_t ch )
{
/* 发送一个字节数据到USART1 */
USART_SendData(pUSARTx,ch);

/* 等待发送完毕 */
while (USART_GetFlagStatus(pUSARTx, USART_FLAG_TXE) == RESET);
}

/*****************  发送字符串 **********************/
void Usart_SendString( USART_TypeDef * pUSARTx, uint8_t *str)
{
unsigned int k=0;
do
{
      Usart_SendByte( pUSARTx, *(str + k) );
      k++;
} while(*(str + k)!='\0');
}

int main(void)
{
u8 times=0;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
My_USART2_Init();

while(1)
{
if(times<=10)
{
Usart_SendString( USART2, (uint8_t *)"ATD18868875103;\r\n" );
times++;
}
}
}