串口(中断设置)
1.中断
1.中断优先级分组
中断优先级分组 | BIN | 抢占优先级 | 响应优先级 |
---|---|---|---|
0 | 111 | 0 位 | 4 位 |
1 | 110 | 1位 | 3位 |
2 | 101 | 2位 | 2位 |
3 | 100 | 3 位 | 1位 |
4 | 011 | 4位 | 0 位 |
(这边很坑,开始学的时候没看到单位,指的是“位”,也就是IP寄存器的高四位分配情况,比如分组3,IP寄存器为0010 0000 指的是抢占优先级为1 响应优先级为0,且数字越小级别越高 )
SCB->AIRCR |=1<<8;//[10:8]
SCB->AIRCR |=1<<10;//101 2组 2位抢 2位响
2.中断初始化 Nvic init()
NVIC->IP[37]=5<<4;//0101 0000
NVIC->ISER[1]|=1<<5; //37位=1使能
NVIC->ISER 使能
- ISER[0]的 bit0~31 分别对应中断
0~31 - ISER[1]的 bit0~32 对应中断 32~63
- ISER[2]的 bit0~3 对应中断 64~67
(使能某个中断,必须设置相应的 ISER 位为 1)
NVIC->IP[] 中断优先级控制的寄存器组 - IP[67]~IP[0]分别对应中断 67~0。
- 每个可屏蔽中断占用 8bit,每个8bit只用了高 4 位
对应的中断号:
WWDG_IRQn = 0, /*!< Window WatchDog Interrupt */
PVD_IRQn = 1, /*!< PVD through EXTI Line detection Interrupt */
TAMPER_IRQn = 2, /*!< Tamper Interrupt */
RTC_IRQn = 3, /*!< RTC global Interrupt */
FLASH_IRQn = 4, /*!< FLASH global Interrupt */
RCC_IRQn = 5, /*!< RCC global Interrupt */
EXTI0_IRQn = 6, /*!< EXTI Line0 Interrupt */
EXTI1_IRQn = 7, /*!< EXTI Line1 Interrupt */
EXTI2_IRQn = 8, /*!< EXTI Line2 Interrupt */
EXTI3_IRQn = 9, /*!< EXTI Line3 Interrupt */
EXTI4_IRQn = 10, /*!< EXTI Line4 Interrupt */
DMA1_Channel1_IRQn = 11, /*!< DMA1 Channel 1 global Interrupt */
DMA1_Channel2_IRQn = 12, /*!< DMA1 Channel 2 global Interrupt */
DMA1_Channel3_IRQn = 13, /*!< DMA1 Channel 3 global Interrupt */
DMA1_Channel4_IRQn = 14, /*!< DMA1 Channel 4 global Interrupt */
DMA1_Channel5_IRQn = 15, /*!< DMA1 Channel 5 global Interrupt */
DMA1_Channel6_IRQn = 16, /*!< DMA1 Channel 6 global Interrupt */
DMA1_Channel7_IRQn = 17, /*!< DMA1 Channel 7 global Interrupt */
ADC1_2_IRQn = 18, /*!< ADC1 and ADC2 global Interrupt */
USB_HP_CAN1_TX_IRQn = 19, /*!< USB Device High Priority or CAN1 TX Interrupts */
USB_LP_CAN1_RX0_IRQn = 20, /*!< USB Device Low Priority or CAN1 RX0 Interrupts */
CAN1_RX1_IRQn = 21, /*!< CAN1 RX1 Interrupt */
CAN1_SCE_IRQn = 22, /*!< CAN1 SCE Interrupt */
EXTI9_5_IRQn = 23, /*!< External Line[9:5] Interrupts */
TIM1_BRK_IRQn = 24, /*!< TIM1 Break Interrupt */
TIM1_UP_IRQn = 25, /*!< TIM1 Update Interrupt */
TIM1_TRG_COM_IRQn = 26, /*!< TIM1 Trigger and Commutation Interrupt */
TIM1_CC_IRQn = 27, /*!< TIM1 Capture Compare Interrupt */
TIM2_IRQn = 28, /*!< TIM2 global Interrupt */
TIM3_IRQn = 29, /*!< TIM3 global Interrupt */
TIM4_IRQn = 30, /*!< TIM4 global Interrupt */
I2C1_EV_IRQn = 31, /*!< I2C1 Event Interrupt */
I2C1_ER_IRQn = 32, /*!< I2C1 Error Interrupt */
I2C2_EV_IRQn = 33, /*!< I2C2 Event Interrupt */
I2C2_ER_IRQn = 34, /*!< I2C2 Error Interrupt */
SPI1_IRQn = 35, /*!< SPI1 global Interrupt */
SPI2_IRQn = 36, /*!< SPI2 global Interrupt */
USART1_IRQn = 37, /*!< USART1 global Interrupt */
USART2_IRQn = 38, /*!< USART2 global Interrupt */
USART3_IRQn = 39, /*!< USART3 global Interrupt */
EXTI15_10_IRQn = 40, /*!< External Line[15:10] Interrupts */
RTCAlarm_IRQn = 41, /*!< RTC Alarm through EXTI Line Interrupt */
USBWakeUp_IRQn = 42, /*!< USB Device WakeUp from suspend through EXTI Line Interrupt */
TIM8_BRK_IRQn = 43, /*!< TIM8 Break Interrupt */
TIM8_UP_IRQn = 44, /*!< TIM8 Update Interrupt */
TIM8_TRG_COM_IRQn = 45, /*!< TIM8 Trigger and Commutation Interrupt */
TIM8_CC_IRQn = 46, /*!< TIM8 Capture Compare Interrupt */
ADC3_IRQn = 47, /*!< ADC3 global Interrupt */
FSMC_IRQn = 48, /*!< FSMC global Interrupt */
SDIO_IRQn = 49, /*!< SDIO global Interrupt */
TIM5_IRQn = 50, /*!< TIM5 global Interrupt */
SPI3_IRQn = 51, /*!< SPI3 global Interrupt */
UART4_IRQn = 52, /*!< UART4 global Interrupt */
UART5_IRQn = 53, /*!< UART5 global Interrupt */
TIM6_IRQn = 54, /*!< TIM6 global Interrupt */
TIM7_IRQn = 55, /*!< TIM7 global Interrupt */
DMA2_Channel1_IRQn = 56, /*!< DMA2 Channel 1 global Interrupt */
DMA2_Channel2_IRQn = 57, /*!< DMA2 Channel 2 global Interrupt */
DMA2_Channel3_IRQn = 58, /*!< DMA2 Channel 3 global Interrupt */
DMA2_Channel4_5_IRQn = 59 /*!< DMA2 Channel 4 and Channel 5 global Interrupt */
2.串口
(相关基础知识见正点原子)
- 除了串口 1 的时钟使能在 APB2ENR 寄存器,其他串口的
时钟使能位都在 APB1ENR 寄存器。
1.串口时钟使能 APB2ENR APB1ENR
- 除了串口 1 的时钟使能在 APB2ENR 寄存器 14口,其他串口的
时钟使能位都在 APB1ENR 寄存器。
RCC->APB2ENR|=1<<2; //使能PORTA口时钟
RCC->APB2ENR|=1<<14; //使能串口时钟
- IO口设置:
GPIOA->CRH&=0XFFFFF00F;//IO状态设置
GPIOA->CRH|=0X000008B0;//IO状态设置
2.串口复位 : APB2RSTR 寄存器
- 一般在系统刚开始配置外设的时候,都会先执行复位该外设的操作
RCC->APB2RSTR|=1<<14; //复位串口1
RCC->APB2RSTR&=~(1<<14);//停止复位
3,串口波特率设置 USART_BRR
USART1->BRR=0x0271; // 波特率设置 115200
4.串口控制 USART_CR1~3
USART1->CR1|=0X202C; //发送接收使能 接收缓冲区非空使能 USART使能
5.数据发送与接收 USART_DR
6.串口状态 USART_SR
- RXNE(读数据寄存器非空
- TC(发送完成)
中断函数
void USART1_IRQHandler(void)
{
u8 res;
if(USART_GetITStatus(USART1,USART_IT_RXNE))//读数据寄存器非空
{
res= USART_ReceiveData(USART1);//接收数据
USART_SendData(USART1,res); //发送
}
}