Posted on November 15, 2011 at 14:41I have been able to successfully setup the ADC3 to set the SR, AWD flag when an input exceeds my threshold set. What I am now looking to do is put the processor in sleep mode (via __WFI();) and then have it wake up via the AWD interrupt.
Here is my ADC setup:
/* Configure ADC3 Channel12 pin as analog input ******************************/
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
GPIO_Init(GPIOC, &GPIO_InitStructure);
/* ADC Common Init **********************************************************/
ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;
ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div2;
ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_Disabled;
ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles;
ADC_CommonInit(&ADC_CommonInitStructure);
/* ADC3 Init ****************************************************************/
ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
ADC_InitStructure.ADC_ScanConvMode = DISABLE;
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfConversion = 1;
ADC_Init(ADC3, &ADC_InitStructure);
/* ADC3 regular channel12 configuration *************************************/
ADC_RegularChannelConfig(ADC3, ADC_Channel_12, 1, ADC_SampleTime_3Cycles);
/* Enable DMA request after last transfer (Single-ADC mode) */
ADC_DMARequestAfterLastTransferCmd(ADC3, ENABLE);
ADC_AnalogWatchdogThresholdsConfig(ADC3, 0x300, 0x0);
ADC_AnalogWatchdogSingleChannelConfig(ADC3, ADC_Channel_12);
ADC_ClearFlag(ADC3, ADC_FLAG_AWD);
ADC_AnalogWatchdogCmd(ADC3, ADC_AnalogWatchdog_SingleRegEnable);
ADC_ITConfig(ADC3, ADC_IT_AWD, ENABLE); // Enable ADC1 AWD interrupt
I then configure the NVIC register as follows:
NVIC_InitTypeDef NVIC_InitStructure;
/* Configure and enable ADC interrupt */
NVIC_InitStructure.NVIC_IRQChannel = ADC_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
When the AWD threshold is met, the processor never wakes up (regardless of ADC input). I'm thinking I don't have an IRQ registered correctly, or I need to setup an IRQ Handler, but I'm not sure where to look for this. Please advise, and thanks.
