一、串口的定義

用來與外界交互數(shù)據(jù)。

二、usart的配置：

1、開啟時鐘。

stm32的usart1掛載在apb2上，USART2、usart3掛載在apb1上。

2、串口的基本配置。

void USART1_Configuration(void)

{

USART_InitTypeDef USART_InitStructure;

USART_DeInit (USART1 );

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_Rx |USART_Mode_Tx ;

USART_Init (USART1 ,&USART_InitStructure );

USART_ClearFlag (USART1 ,USART_FLAG_TC );

USART_ITConfig (USART1 ,USART_IT_RXNE ,ENABLE );

USART_Cmd (USART1 ,ENABLE );

}

3、中斷向量表的配置。

void NVIC_Configuration(void)

{

NVIC_InitTypeDef NVIC_InitStructure;

NVIC_PriorityGroupConfig (NVIC_PriorityGroup_1);

NVIC_InitStructure .NVIC_IRQChannel =USART1_IRQn ;

NVIC_InitStructure .NVIC_IRQChannelPreemptionPriority =0;

NVIC_InitStructure .NVIC_IRQChannelSubPriority =1;

NVIC_InitStructure .NVIC_IRQChannelCmd =ENABLE ;

NVIC_Init(&NVIC_InitStructure );

}

4、串口中斷函數(shù)的書寫。

void USART1_IRQHandler(void )

{

if(USART_GetFlagStatus (USART1 ,USART_IT_RXNE) !=RESET )

{

USART_ClearITPendingBit (USART1 ,USART_IT_RXNE );

USART1_RX_Buffer=USART_ReceiveData (USART1 );

GPIO_SetBits (GPIOC ,GPIO_Pin_12 );

}

}