MCU 在 STOP 状态下通过 UART 唤醒分 析

int main(void)

{

#ifdef DEBUG

debug();

#endif

// System Init...

System_Init();

PWR_DeInit();

UART_Init();

// Global Variables Init...

Global_Variables_Init(); // + by dsg for global variables init...

while(1)

{

/* Request to enter STOP mode with regulator in low power mode*/

PWR_EnterSTOPMode(PWR_Regulator_LowPower, PWR_STOPEntry_WFI);

}

}

void EXTIX_Init(void)

{

EXTI_InitTypeDef EXTI_InitStructure;

NVIC_InitTypeDef NVIC_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);

GPIO_EXTILineConfig(GPIO_PortSourceGPIOB,GPIO_PinSource11);

EXTI_InitStructure.EXTI_Line=EXTI_Line11; //GPIOA.3 UART2_RX

EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;

EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;

EXTI_InitStructure.EXTI_LineCmd = ENABLE;

EXTI_Init(&EXTI_InitStructure);

NVIC_InitStructure.NVIC_IRQChannel = EXTI15_10_IRQChannel;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x01;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

}

/*******************************************************************************

* Function Name : EXTI15_10_IRQHandler

* Description : This function handles External lines 15 to 10 interrupt request.

* Input : None

* Output : None

* Return : None

*******************************************************************************/

void EXTI15_10_IRQHandler(void)

{

EXTI_ClearITPendingBit(EXTI_Line11);

NVIC_GenerateSystemReset();

}

void PWR_EnterSTOPMode(u32 PWR_Regulator, u8 PWR_STOPEntry)

{

// Change the UART RX PIN to external interrupt mode

EXTIX_Init();

GPIO_ResetBits(GPIOC, GPIO_Pin_6);

GPIO_ResetBits(GPIOC, GPIO_Pin_7);

GPIO_ResetBits(GPIOC, GPIO_Pin_8);

u32 tmpreg = 0;

/* Check the parameters */

assert_param(IS_PWR_REGULATOR(PWR_Regulator));

assert_param(IS_PWR_STOP_ENTRY(PWR_STOPEntry));

/* Select the regulator state in STOP mode ---------------------------------*/

tmpreg = PWR->CR;

/* Clear PDDS and LPDS bits */

tmpreg &= CR_DS_Mask;

/* Set LPDS bit according to PWR_Regulator value */

tmpreg |= PWR_Regulator;

/* Store the new value */

PWR->CR = tmpreg;

/* Set SLEEPDEEP bit of Cortex System Control Register */

*(vu32 *) SCB_SysCtrl |= SysCtrl_SLEEPDEEP_Set;

/* Select STOP mode entry --------------------------------------------------*/

if(PWR_STOPEntry == PWR_STOPEntry_WFI)

{

/* Request Wait For Interrupt */

__WFI();

}

else

{

/* Request Wait For Event */

__WFE();

}

}

void UART_Init(void)

{

GPIO_InitTypeDef GPIO_InitStructure;

USART_InitTypeDef USART_InitStructure;

NVIC_InitTypeDef NVIC_InitStructure;

/* Enable USART3 clock */

RCC_APB1PeriphClockCmd( RCC_APB1Periph_USART3, ENABLE);

// GPIO Settings for USART3

// PB10: TXD_ROOM

GPIO_StructInit(&GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;

GPIO_Init(GPIOB, &GPIO_InitStructure);

// PB11: RXD_ROOM

GPIO_StructInit(&GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;

//GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;

GPIO_Init(GPIOB, &GPIO_InitStructure);

/* USARTx configuration ------------------------------------------------------*/

/* USARTx configured as follow:

- BaudRate = 600 baud

- Word Length = 8 Bits

- Two Stop Bit

- Even parity

- Hardware flow control disabled (RTS and CTS signals)

- Receive and transmit enabled

*/

USART_DeInit(USART3);

USART_InitStructure.USART_BaudRate =9600;

USART_InitStructure.USART_WordLength = USART_WordLength_9b;

USART_InitStructure.USART_StopBits = USART_StopBits_2;

USART_InitStructure.USART_Parity = USART_Parity_Even;

USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;

USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;

USART_Init(USART3, &USART_InitStructure);

UartRxON();

// In initial state, waiting for indoor data...

USART_ITConfig(USART3, USART_IT_TXE, DISABLE);

USART_ITConfig(USART3, USART_IT_RXNE, ENABLE);

UART_State=UART_RX; //0; // 0: received state 1: transmit state

/* Enable the USART3 Interrupt */

NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQChannel;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

/* Enable USART3 */

USART_Cmd(USART3, ENABLE);

}