STM32开发笔记28: 中断请求的移植与处理
单片机型号：STM32L053R8T6
本文介绍如何移植STM32的IRQ（中断请求）到自己的系统中，我们以USART1接收中断为例。
先看启动文件（汇编语言），如下列程序所示，列出了其向量区，USART1的中断向量已用红色标识，当和USART1相关的中断发生时，程序指针（PC）在保护现场后，直接指向到该向量。
__Vectors DCD __initial_sp ; Top of Stack
DCD Reset_Handler ; Reset Handler
DCD NMI_Handler ; NMI Handler
DCD HardFault_Handler ; Hard Fault Handler
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD SVC_Handler ; SVCall Handler
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD PendSV_Handler ; PendSV Handler
DCD SysTick_Handler ; SysTick Handler
; External Interrupts
DCD WWDG_IRQHandler ; Window Watchdog
DCD PVD_IRQHandler ; PVD through EXTI Line detect
DCD RTC_IRQHandler ; RTC through EXTI Line
DCD FLASH_IRQHandler ; FLASH
DCD RCC_CRS_IRQHandler ; RCC and CRS
DCD EXTI0_1_IRQHandler ; EXTI Line 0 and 1
DCD EXTI2_3_IRQHandler ; EXTI Line 2 and 3
DCD EXTI4_15_IRQHandler ; EXTI Line 4 to 15
DCD TSC_IRQHandler ; TSC
DCD DMA1_Channel1_IRQHandler ; DMA1 Channel 1
DCD DMA1_Channel2_3_IRQHandler ; DMA1 Channel 2 and Channel 3
DCD DMA1_Channel4_5_6_7_IRQHandler ; DMA1 Channel 4, Channel 5, Channel 6 and Channel 7
DCD ADC1_COMP_IRQHandler ; ADC1, COMP1 and COMP2
DCD LPTIM1_IRQHandler ; LPTIM1
DCD 0 ; Reserved
DCD TIM2_IRQHandler ; TIM2
DCD 0 ; Reserved
DCD TIM6_DAC_IRQHandler ; TIM6 and DAC
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD TIM21_IRQHandler ; TIM21
DCD 0 ; Reserved
DCD TIM22_IRQHandler ; TIM22
DCD I2C1_IRQHandler ; I2C1
DCD I2C2_IRQHandler ; I2C2
DCD SPI1_IRQHandler ; SPI1
DCD SPI2_IRQHandler ; SPI2
DCD USART1_IRQHandler ; USART1
DCD USART2_IRQHandler ; USART2
DCD RNG_LPUART1_IRQHandler ; RNG and LPUART1
DCD LCD_IRQHandler ; LCD
DCD USB_IRQHandler ; USB
__Vectors_EndDCD USART1_IRQHandler ; USART1
DCD USART2_IRQHandler ; USART2
DCD RNG_LPUART1_IRQHandler ; RNG and LPUART1
DCD LCD_IRQHandler ; LCD
DCD USB_IRQHandler ; USB
__Vectors_End此时，我们需做2件事情，在驱动的头文件中定义该向量的函数原型，在驱动的C文件中完成该向量的函数实现。STM32CubeMX会有相应的中断处理，我们直接调用就好，这个可以参照STM32提供的样例文件，如下列程序所示。
void USART1_IRQHandler(void)
{
HAL_UART_IRQHandler(pUART1);
}后面的事情交由STM32CubeMX提供的驱动函数进行处理，我们慢慢看。HAL_UART_IRQHandler函数对中断进行处理，然后根据相应的中断类型，再调用相关的驱动函数，我们这里就需调用UART_Receive_IT函数，已用红色标识。
void HAL_UART_IRQHandler(UART_HandleTypeDef *huart)
{
uint32_t isrflags = READ_REG(huart->Instance->ISR);
uint32_t cr1its = READ_REG(huart->Instance->CR1);
uint32_t cr3its;
uint32_t errorflags;
/* If no error occurs */
errorflags = (isrflags & (uint32_t)(USART_ISR_PE | USART_ISR_FE | USART_ISR_ORE | USART_ISR_NE));
if (errorflags == RESET)
{
/* UART in mode Receiver ---------------------------------------------------*/
if(((isrflags & USART_ISR_RXNE) != RESET) && ((cr1its & USART_CR1_RXNEIE) != RESET))
{
UART_Receive_IT(huart);
return;
}
}
/* If some errors occur */
cr3its = READ_REG(huart->Instance->CR3);
if( (errorflags != RESET)
&& ( ((cr3its & USART_CR3_EIE) != RESET)
|| ((cr1its & (USART_CR1_RXNEIE | USART_CR1_PEIE)) != RESET)) )
{
/* UART parity error interrupt occurred -------------------------------------*/
if(((isrflags & USART_ISR_PE) != RESET) && ((cr1its & USART_CR1_PEIE) != RESET))
{
__HAL_UART_CLEAR_IT(huart, UART_CLEAR_PEF);
huart->ErrorCode |= HAL_UART_ERROR_PE;
}
/* UART frame error interrupt occurred --------------------------------------*/
if(((isrflags & USART_ISR_FE) != RESET) && ((cr3its & USART_CR3_EIE) != RESET))
{
__HAL_UART_CLEAR_IT(huart, UART_CLEAR_FEF);
huart->ErrorCode |= HAL_UART_ERROR_FE;
}
/* UART noise error interrupt occurred --------------------------------------*/
if(((isrflags & USART_ISR_NE) != RESET) && ((cr3its & USART_CR3_EIE) != RESET))
{
__HAL_UART_CLEAR_IT(huart, UART_CLEAR_NEF);
huart->ErrorCode |= HAL_UART_ERROR_NE;
}
/* UART Over-Run interrupt occurred -----------------------------------------*/
if(((isrflags & USART_ISR_ORE) != RESET) &&
(((cr1its & USART_CR1_RXNEIE) != RESET) || ((cr3its & USART_CR3_EIE) != RESET)))
{
__HAL_UART_CLEAR_IT(huart, UART_CLEAR_OREF);
huart->ErrorCode |= HAL_UART_ERROR_ORE;
}
/* Call UART Error Call back function if need be --------------------------*/
if(huart->ErrorCode != HAL_UART_ERROR_NONE)
{
/* UART in mode Receiver ---------------------------------------------------*/
if(((isrflags & USART_ISR_RXNE) != RESET) && ((cr1its & USART_CR1_RXNEIE) != RESET))
{
void UART_Receive_IT(huart);
}
/* If Overrun error occurs, or if any error occurs in DMA mode reception,
consider error as blocking */
if (((huart->ErrorCode & HAL_UART_ERROR_ORE) != RESET) ||
(HAL_IS_BIT_SET(huart->Instance->CR3, USART_CR3_DMAR)))
{
/* Blocking error : transfer is aborted
Set the UART state ready to be able to start again the process,
Disable Rx Interrupts, and disable Rx DMA request, if ongoing */
UART_EndRxTransfer(huart);
/* Disable the UART DMA Rx request if enabled */
if (HAL_IS_BIT_SET(huart->Instance->CR3, USART_CR3_DMAR))
{
CLEAR_BIT(huart->Instance->CR3, USART_CR3_DMAR);
/* Abort the UART DMA Rx channel */
if(huart->hdmarx != NULL)
{
/* Set the UART DMA Abort callback :
will lead to call HAL_UART_ErrorCallback() at end of DMA abort procedure */
huart->hdmarx->XferAbortCallback = UART_DMAAbortOnError;
/* Abort DMA RX */
if(HAL_DMA_Abort_IT(huart->hdmarx) != HAL_OK)
{
/* Call Directly huart->hdmarx->XferAbortCallback function in case of error */
huart->hdmarx->XferAbortCallback(huart->hdmarx);
}
}
else
{
/* Call user error callback */
HAL_UART_ErrorCallback(huart);
}
}
else
{
/* Call user error callback */
HAL_UART_ErrorCallback(huart);
}
}
else
{
/* Non Blocking error : transfer could go on.
Error is notified to user through user error callback */
HAL_UART_ErrorCallback(huart);
huart->ErrorCode = HAL_UART_ERROR_NONE;
}
}
return;
} /* End if some error occurs */
/* UART wakeup from Stop mode interrupt occurred ---------------------------*/
if(((isrflags & USART_ISR_WUF) != RESET) && ((cr3its & USART_CR3_WUFIE) != RESET))
{
__HAL_UART_CLEAR_IT(huart, UART_CLEAR_WUF);
/* Set the UART state ready to be able to start again the process */
huart->gState = HAL_UART_STATE_READY;
huart->RxState = HAL_UART_STATE_READY;
HAL_UARTEx_WakeupCallback(huart);
return;
}
/* UART in mode Transmitter ------------------------------------------------*/
if(((isrflags & USART_ISR_TXE) != RESET) && ((cr1its & USART_CR1_TXEIE) != RESET))
{
UART_Transmit_IT(huart);
return;
}
/* UART in mode Transmitter (transmission end) -----------------------------*/
if(((isrflags & USART_ISR_TC) != RESET) && ((cr1its & USART_CR1_TCIE) != RESET))
{
UART_EndTransmit_IT(huart);
return;
}
}void UART_Receive_IT(huart);
}
/* If Overrun error occurs, or if any error occurs in DMA mode reception,
consider error as blocking */
if (((huart->ErrorCode & HAL_UART_ERROR_ORE) != RESET) ||
(HAL_IS_BIT_SET(huart->Instance->CR3, USART_CR3_DMAR)))
{
/* Blocking error : transfer is aborted
Set the UART state ready to be able to start again the process,
Disable Rx Interrupts, and disable Rx DMA request, if ongoing */
UART_EndRxTransfer(huart);
/* Disable the UART DMA Rx request if enabled */
if (HAL_IS_BIT_SET(huart->Instance->CR3, USART_CR3_DMAR))
{
CLEAR_BIT(huart->Instance->CR3, USART_CR3_DMAR);
/* Abort the UART DMA Rx channel */
if(huart->hdmarx != NULL)
{
/* Set the UART DMA Abort callback :
will lead to call HAL_UART_ErrorCallback() at end of DMA abort procedure */
huart->hdmarx->XferAbortCallback = UART_DMAAbortOnError;
/* Abort DMA RX */
if(HAL_DMA_Abort_IT(huart->hdmarx) != HAL_OK)
{
/* Call Directly huart->hdmarx->XferAbortCallback function in case of error */
huart->hdmarx->XferAbortCallback(huart->hdmarx);
}
}
else
{
/* Call user error callback */
HAL_UART_ErrorCallback(huart);
}
}
else
{
/* Call user error callback */
HAL_UART_ErrorCallback(huart);
}
}
else
{
/* Non Blocking error : transfer could go on.
Error is notified to user through user error callback */
HAL_UART_ErrorCallback(huart);
huart->ErrorCode = HAL_UART_ERROR_NONE;
}
}
return;
} /* End if some error occurs */
/* UART wakeup from Stop mode interrupt occurred ---------------------------*/
if(((isrflags & USART_ISR_WUF) != RESET) && ((cr3its & USART_CR3_WUFIE) != RESET))
{
__HAL_UART_CLEAR_IT(huart, UART_CLEAR_WUF);
/* Set the UART state ready to be able to start again the process */
huart->gState = HAL_UART_STATE_READY;
huart->RxState = HAL_UART_STATE_READY;
HAL_UARTEx_WakeupCallback(huart);
return;
}
/* UART in mode Transmitter ------------------------------------------------*/
if(((isrflags & USART_ISR_TXE) != RESET) && ((cr1its & USART_CR1_TXEIE) != RESET))
{
UART_Transmit_IT(huart);
return;
}
/* UART in mode Transmitter (transmission end) -----------------------------*/
if(((isrflags & USART_ISR_TC) != RESET) && ((cr1its & USART_CR1_TCIE) != RESET))
{
UART_EndTransmit_IT(huart);
return;
}
}下面是UART_Receive_IT函数，里面有一个以Callback结尾的函数，已用红色标识，这就是STM32CubeMX留给我们的回调函数，我们只需将自己的逻辑写入该函数即可。而且该函数是用__weak进行修饰的，也就是说，我们只需在自己的文件中直接处理该函数即可。
static HAL_StatusTypeDef UART_Receive_IT(UART_HandleTypeDef *huart)
{
uint16_t* tmp;
uint16_t uhMask = huart->Mask;
uint16_t uhdata;
/* Check that a Rx process is ongoing */
if(huart->RxState == HAL_UART_STATE_BUSY_RX)
{
uhdata = (uint16_t) READ_REG(huart->Instance->RDR);
if ((huart->Init.WordLength == UART_WORDLENGTH_9B) && (huart->Init.Parity == UART_PARITY_NONE))
{
tmp = (uint16_t*) huart->pRxBuffPtr ;
*tmp = (uint16_t)(uhdata & uhMask);
huart->pRxBuffPtr +=2;
}
else
{
*huart->pRxBuffPtr++ = (uint8_t)(uhdata & (uint8_t)uhMask);
}
if(--huart->RxXferCount == 0U)
{
/* Disable the UART Parity Error Interrupt and RXNE interrupt*/
CLEAR_BIT(huart->Instance->CR1, (USART_CR1_RXNEIE | USART_CR1_PEIE));
/* Disable the UART Error Interrupt: (Frame error, noise error, overrun error) */
CLEAR_BIT(huart->Instance->CR3, USART_CR3_EIE);
/* Rx process is completed, restore huart->RxState to Ready */
huart->RxState = HAL_UART_STATE_READY;
HAL_UART_RxCpltCallback(huart);
return HAL_OK;
}
return HAL_OK;
}
else
{
/* Clear RXNE interrupt flag */
__HAL_UART_SEND_REQ(huart, UART_RXDATA_FLUSH_REQUEST);
return HAL_BUSY;
}
}HAL_UART_RxCpltCallback(huart);
return HAL_OK;
}
return HAL_OK;
}
else
{
/* Clear RXNE interrupt flag */
__HAL_UART_SEND_REQ(huart, UART_RXDATA_FLUSH_REQUEST);
return HAL_BUSY;
}
}总结一下，如何移植和处理中断函数。
（1）在自己的驱动文件的头文件中，加入需要处理的中断矢量函数的函数原型声明。
（2）在自己的驱动文件的C文件中，对该函数进行处理，要调用STM32CubeMX提供的驱动文件进行处理。
（3）在自己的驱动文件的C文件中，直接对相应的回调函数进行处理，加入逻辑即可。
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CSDN：http://blog.csdn.net/qingwufeiyang12346