STM32 UART DMA实现未知数据长度接收

/**

* [url=home.php?mod=space&uid=247401]@brief[/url] Configures the system EXIT.

* @param None

* @retval None

*/

void EXTI_Configuration(void)

{

EXTI_InitTypeDef EXTI_InitStructure;

/* Connect EXTI8 Line to PB.07 pin */

GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource7);

/* Configure EXTI8 line */

EXTI_InitStructure.EXTI_Line = EXTI_Line7;

EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;

EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;

EXTI_InitStructure.EXTI_LineCmd = ENABLE;

EXTI_Init(&EXTI_InitStructure);

/* Clears EXTI line pending bits. */

EXTI_ClearITPendingBit(EXTI_Line7);

}

/**

* @brief Configures NVIC and Vector Table base location.

* @param None

* @retval : None

*/

void NVIC_Configuration(void)

{

NVIC_InitTypeDef NVIC_InitStructure;

/* Configure the NVIC Preemption Priority Bits*/

NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);

/* Set the Vector Table base location at 0x08000000 */

NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);

/* Enable the DMA1_Channel_Rx Interrupt */

NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel5_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

/* Configure DMA1_Channel_Tx interrupt */

NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel4_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

/* Configure TIM1 update interrupt */

NVIC_InitStructure.NVIC_IRQChannel = TIM4_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 5;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

/* Enable and set EXTI9_5 Interrupt to the lowest priority */

NVIC_InitStructure.NVIC_IRQChannel = EXTI9_5_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 6;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

}

/*

* This function is called by timer_init() to perform the non-generic portion

* of the initialization of the timer module.

*/

void timer_init_non_generic(void)

{

TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;

TIM_OCInitTypeDef TIM_OCInitStructure;

TIM_ICInitTypeDef TIM_ICInitStructure;

/* TIM4 configuration ----------------------------------------------------*/

TIM_TimeBaseStructure.TIM_Period = 65535;

TIM_TimeBaseStructure.TIM_Prescaler = SystemCoreClock/1000000 * 1000 - 1; TIM_TimeBaseStructure.TIM_ClockDivision = 0;

TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;

TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;

TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure);

/* Output Compare Mode configuration: Channel1 */

TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_Timing;

TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Disable;

TIM_OCInitStructure.TIM_Pulse = 20;

TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;

TIM_OC1Init(TIM4, &TIM_OCInitStructure);

/* TIM4 Channel 2 Input Capture Configuration */

TIM_ICInitStructure.TIM_Channel = TIM_Channel_2;

TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;

TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;

TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;

TIM_ICInitStructure.TIM_ICFilter = 0;

TIM_ICInit(TIM4, &TIM_ICInitStructure);

/* TIM4 Input trigger configuration: External Trigger connected to TI2 */

TIM_SelectInputTrigger(TIM4, TIM_TS_TI2FP2);

/* TIM4 configuration in slave reset mode where the timer counter is

re-initialied in response to rising edges on an input capture (TI2) */

TIM_SelectSlaveMode(TIM4, TIM_SlaveMode_Reset);

/* TIM4 IT CC1 enable */

TIM_ITConfig(TIM4, TIM_IT_CC1, ENABLE);

}