STM32 serial port usart1 routine

 

  One 、 Enable in main function GPIOA, and USART1

void My_USART1_Init(void)
{
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);
}

  because USART1 Is to reuse GPIOA So enable GPIOA

For... Under the reuse function GPIO How to determine the mode , This needs to be checked 《 Chinese Reference Manual V10》 P110 Table for “8.1.11 Peripheral GPIO To configure ”. Configure full duplex serial port 1, that TX(PA9) The pin needs to be configured as push-pull multiplex output , RX(PA10) The pins are configured as floating input or with pull-up input .

  Two 、IO Mouth initialization

void My_USART1_Init(void)
{
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);
	
	GPIO_InitTypeDef GPIO_InitStruct;
	
	GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP;
	GPIO_InitStruct.GPIO_Pin = GPIO_Pin_8;
	GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA,&GPIO_InitStruct);
	
	GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IN_FLOATING;
	GPIO_InitStruct.GPIO_Pin = GPIO_Pin_10;
	GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA,&GPIO_InitStruct);
}

3、 ... and 、 Serial initialization

void My_USART1_Init(void)
{
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);
	
	GPIO_InitTypeDef GPIO_InitStruct;
	USART_InitTypeDef USART_InitStruct;
	
	GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP;
	GPIO_InitStruct.GPIO_Pin = GPIO_Pin_8;
	GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA,&GPIO_InitStruct);
	
	GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IN_FLOATING;
	GPIO_InitStruct.GPIO_Pin = GPIO_Pin_10;
	GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA,&GPIO_InitStruct);
	
	USART_InitStruct.USART_BaudRate = 115200;
	USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
	USART_InitStruct.USART_Mode = USART_Mode_Rx|USART_Mode_Tx;
	USART_InitStruct.USART_Parity = USART_Parity_No;
	USART_InitStruct.USART_StopBits = USART_StopBits_1;
	USART_InitStruct.USART_WordLength = USART_WordLength_8b;
	
	USART_Init(USART1,&USART_InitStruct);
}

Four 、 Enable serial port 1

Put it in the serial port initialization function .

USART_Cmd(USART1,ENABLE);

5、 ... and 、 Open interrupt

USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);

Here we use USART_IT_RXNE, The receive buffer is not empty , As long as you receive the data , Start the interrupt service function .

6、 ... and 、 Interrupt priority grouping

Sub priority = Response priority

NVIC_InitTypeDef NVIC_InitStruct;

NVIC_InitStruct.NVIC_IRQChannel = USART1_IRQn;// stay stm32f10x.h Inside looking for IRQn At the end of the 
NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;// Whether to open the interrupt channel 
NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 1; // preemption 
NVIC_InitStruct.NVIC_IRQChannelSubPriority = 1;// Sub priority = Response priority 
NVIC_Init(&NVIC_InitStruct);// Set the corresponding interrupt preemption priority and response priority .

7、 ... and 、 Interrupt service function

void USART1_IRQHandler(void)// Interrupt service function , It's the startup file startup_stm32f10x_hd.s It's defined in 
{
	u8 res;
	if(USART_GetITStatus(USART1,USART_IT_RXNE))
	{
		res = USART_ReceiveData(USART1);
		USART_SendData(USART1,res);
	}
}