[STM32F4] STM32F407学习2--内部外设初始化

void LED_Init(void)

{

  GPIO_InitTypeDef  GPIO_InitStructure;

  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);//使能GPIOF时钟

  //GPIOF9,F10初始化设置

  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12 | GPIO_Pin_10;

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;//普通输出模式

  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//推挽输出

  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;//100MHz

  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;//上拉

  GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIO

}

void uart_init(u32 bound)

{

GPIO_InitTypeDef GPIO_InitStructure;

USART_InitTypeDef USART_InitStructure;

NVIC_InitTypeDef NVIC_InitStructure;

//GPIOA 和 USART1 时钟使能①

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE); //使能 GPIOA 时钟

RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);//使能 USART1 时钟

//USART_DeInit(USART1); //复位串口 1 ②

GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_USART1); //PA9 复用为 USART1

GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_USART1); //PA10 复用为 USART1

//USART1_TX PA.9 PA.10 ③

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10; //GPIOA9 与 GPIOA10

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//复用功能

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //速度 50MHz

GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //推挽复用输出

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; //上拉

GPIO_Init(GPIOA,&GPIO_InitStructure); //初始化 PA9， PA10

//USART 初始化设置 ④

USART_InitStructure.USART_BaudRate = bound;//一般设置为 9600;

USART_InitStructure.USART_WordLength = USART_WordLength_8b;//字长为 8 位数据格式

USART_InitStructure.USART_StopBits = USART_StopBits_1;//一个停止位

USART_InitStructure.USART_Parity = USART_Parity_No;//无奇偶校验位

USART_InitStructure.USART_HardwareFlowControl =USART_HardwareFlowControl_None;

USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //收发模式

USART_Init(USART1, &USART_InitStructure); //初始化串口

#if EN_USART1_RX //NVIC 设置，使能中断 ⑤

USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);//开启中断

//Usart1 NVIC 配置

NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=2;//抢占优先级 2

NVIC_InitStructure.NVIC_IRQChannelSubPriority =2; //响应优先级 2

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ 通道使能

NVIC_Init(&NVIC_InitStructure); //根据指定的参数初始化 VIC 寄存器、

#endif

USART_Cmd(USART1, ENABLE); //使能串口 ⑥

} 

void TIM3_Int_Init(u16 arr,u16 psc)

{

TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;

NVIC_InitTypeDef NVIC_InitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE); //①使能 TIM3 时钟

TIM_TimeBaseInitStructure.TIM_Period = arr; //自动重装载值

TIM_TimeBaseInitStructure.TIM_Prescaler=psc; //定时器分频

TIM_TimeBaseInitStructure.TIM_CounterMode=TIM_CounterMode_Up; //向上计数模式

TIM_TimeBaseInitStructure.TIM_ClockDivision=TIM_CKD_DIV1;

TIM_TimeBaseInit(TIM3,&TIM_TimeBaseInitStructure);// ②初始化定时器 TIM3

TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE); //③允许定时器 3 更新中断

NVIC_InitStructure.NVIC_IRQChannel=TIM3_IRQn; //定时器 3 中断

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=0x01; //抢占优先级 1

NVIC_InitStructure.NVIC_IRQChannelSubPriority=0x03; //响应优先级 3

NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;

NVIC_Init(&NVIC_InitStructure);// ④初始化 NVIC

TIM_Cmd(TIM3,ENABLE); //⑤使能定时器 3

}

//定时器 3 中断服务函数

void TIM3_IRQHandler(void)

{

if(TIM_GetITStatus(TIM3,TIM_IT_Update)==SET) //溢出中断

{

LED1=!LED1;

}

TIM_ClearITPendingBit(TIM3,TIM_IT_Update); //清除中断标志位

}