/**
* @brief Start Bit Method to Wake Up USART from Stop mode Test.
* @param None
* @retval None
*/
static void WakeUp_StartBitMethod(void)
{
/* Configure the wake up Method = Start bit */
USART_StopModeWakeUpSourceConfig(USART1, USART_WakeUpSource_StartBit);
/* Enable USART1 */
USART_Cmd(USART1, ENABLE);
/* Before entering the USART in STOP mode the REACK flag must be checked to ensure the USART RX is ready */
while(USART_GetFlagStatus(USART1, USART_FLAG_REACK) == RESET)
{}
/* Enable USART STOP mode by setting the UESM bit in the CR1 register.*/
USART_STOPModeCmd(USART1, ENABLE);
/* Enable the wake up from stop Interrupt */
USART_ITConfig(USART1, USART_IT_WU, ENABLE);
/* Enable PWR APB clock */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE);
/* Enter USART in STOP mode with regulator in low power mode */
PWR_EnterSTOPMode(PWR_Regulator_LowPower, PWR_STOPEntry_WFI);
/* Waiting Wake Up interrupt */
while(InterruptCounter == 0x00)
{}
/* Disable USART peripheral in STOP mode */
USART_STOPModeCmd(USART1, DISABLE);
while(USART_GetFlagStatus(USART1, USART_FLAG_RXNE) == RESET)
{}
DataReceived = USART_ReceiveData(USART1);
/* Clear the TE bit (if a transmission is on going or a data is in the TDR, it will be sent before
efectivelly disabling the transmission) */
USART_DirectionModeCmd(USART1, USART_Mode_Tx, DISABLE);
/* Check the Transfer Complete Flag */
while (USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET)
{}
/* USART Disable */
USART_Cmd(USART1, DISABLE);
}
/**
* @brief Main program.
* @param None
* @retval None
*/
int main(void)
{
/*!< At this stage the microcontroller clock setting is already configured,
this is done through SystemInit() function which is called from startup
file (startup_stm32f30x.s) before to branch to application main.
To reconfigure the default setting of SystemInit() function, refer to
system_stm32f30x.c file
*/
/* Initialize LEDs available on STM32303C-EVAL board ************************/
STM_EVAL_LEDInit(LED1);
STM_EVAL_LEDInit(LED2);
STM_EVAL_LEDInit(LED3);
STM_EVAL_LEDInit(LED4);
/* Enable PWR APB clock */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE);
/* USART configuration to Wake up from STOP mode by Start bit Method */
USART_Config();
/* Waiting Wake Up interrupt */
while(InterruptCounter == 0x00)
{}
/* Disable USART peripheral in STOP mode */
USART_STOPModeCmd(USART1, DISABLE);
while(USART_GetFlagStatus(USART1, USART_FLAG_RXNE) == RESET)
{}
DataReceived = USART_ReceiveData(USART1);
/* Clear the TE bit (if a transmission is on going or a data is in the TDR, it will be sent before
effectively disabling the transmission) */
USART_DirectionModeCmd(USART1, USART_Mode_Tx, DISABLE);
/* Check the Transfer Complete Flag */
while (USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET)
{}
/* USART Disable */
USART_Cmd(USART1, DISABLE);
/* Configure SystemClock*/
RestoreConfiguration();
/* Configure and enable the systick timer to generate an interrupt each 1 ms */
SysTick_Config((SystemCoreClock / 1000));
while(1)
{}
}
/**
* @brief Configure the USART to Wake up from STOP mode by Start bit Method
* @param None
* @retval None
*/
static void USART_Config(void)
{
USART_InitTypeDef USART_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
/* Enable GPIOD clock */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOC|RCC_AHBPeriph_GPIOE , ENABLE);
/* Enable USART1 APB clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
/* Configure the HSI as USART clock */
RCC_USARTCLKConfig(RCC_USART1CLK_HSI);
/* USART1 Pins configuration ***********************************************/
/* Connect pin to Periph */
GPIO_PinAFConfig(GPIOC, GPIO_PinSource4, GPIO_AF_7);
GPIO_PinAFConfig(GPIOE, GPIO_PinSource1, GPIO_AF_7);
/* Configure pins as AF pushpull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOC, &GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1;
GPIO_Init(GPIOE, &GPIO_InitStructure);
/* USARTx configured as follow:
- BaudRate = 115200 baud
- Word Length = 8 Bits
- Stop Bit = 1 Stop Bit
- Parity = No Parity
- Hardware flow control disabled (RTS and CTS signals)
- Receive and transmit enabled
*/
USART_DeInit(USART1);
USART_InitStructure.USART_BaudRate = 115200;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;
USART_InitStructure.USART_StopBits = USART_StopBits_1;
USART_InitStructure.USART_Parity = USART_Parity_No;
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
USART_Init(USART1, &USART_InitStructure);
/* USART2 IRQ Channel configuration */
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x01;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* Configure the wake up Method = Start bit */
USART_StopModeWakeUpSourceConfig(USART1, USART_WakeUpSource_StartBit);
/* Enable USART1 */
USART_Cmd(USART1, ENABLE);
/* Before entering the USART in STOP mode the REACK flag must be checked to ensure the USART RX is ready */
while(USART_GetFlagStatus(USART1, USART_FLAG_REACK) == RESET)
{}
/* Enable USART STOP mode by setting the UESM bit in the CR1 register.*/
USART_STOPModeCmd(USART1, ENABLE);
/* Enable the wake up from stop Interrupt */
USART_ITConfig(USART1, USART_IT_WU, ENABLE);
/* Enter USART in STOP mode with regulator in low power mode */
PWR_EnterSTOPMode(PWR_Regulator_LowPower, PWR_STOPEntry_WFI);
}
