Hello, I need help with ADC and DMA settings. My application is VERY EASY but I do not understand the setup parameters. The application is that I just start CPU and the ADC raw value should independently transfer via DMA to variable. When I need the value (randomly) I just read the internal variable. I saw several youtube manuals but I still have 0 on output even when there is 1V. I use PA0 pin (ADC1, chan 0) on very easy CPU STM32G031. I need to use DMA Channel 4 (Channel 1 and 2 are used for USART_RX and TX)
My setup:
The generated code is like this (I use LL):
static void MX_ADC1_Init(void)
{
/* USER CODE BEGIN ADC1_Init 0 */
/* USER CODE END ADC1_Init 0 */
LL_ADC_InitTypeDef ADC_InitStruct = {0};
LL_ADC_REG_InitTypeDef ADC_REG_InitStruct = {0};
LL_GPIO_InitTypeDef GPIO_InitStruct = {0};
/* Peripheral clock enable */
LL_APB2_GRP1_EnableClock(LL_APB2_GRP1_PERIPH_ADC);
LL_IOP_GRP1_EnableClock(LL_IOP_GRP1_PERIPH_GPIOA);
/**ADC1 GPIO Configuration
PA0 ------> ADC1_IN0
*/
GPIO_InitStruct.Pin = LL_GPIO_PIN_0;
GPIO_InitStruct.Mode = LL_GPIO_MODE_ANALOG;
GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
LL_GPIO_Init(GPIOA, &GPIO_InitStruct);
/* ADC1 DMA Init */
/* ADC1 Init */
LL_DMA_SetPeriphRequest(DMA1, LL_DMA_CHANNEL_4, LL_DMAMUX_REQ_ADC1);
LL_DMA_SetDataTransferDirection(DMA1, LL_DMA_CHANNEL_4, LL_DMA_DIRECTION_PERIPH_TO_MEMORY);
LL_DMA_SetChannelPriorityLevel(DMA1, LL_DMA_CHANNEL_4, LL_DMA_PRIORITY_LOW);
LL_DMA_SetMode(DMA1, LL_DMA_CHANNEL_4, LL_DMA_MODE_CIRCULAR);
LL_DMA_SetPeriphIncMode(DMA1, LL_DMA_CHANNEL_4, LL_DMA_PERIPH_NOINCREMENT);
LL_DMA_SetMemoryIncMode(DMA1, LL_DMA_CHANNEL_4, LL_DMA_MEMORY_INCREMENT);
LL_DMA_SetPeriphSize(DMA1, LL_DMA_CHANNEL_4, LL_DMA_PDATAALIGN_WORD);
LL_DMA_SetMemorySize(DMA1, LL_DMA_CHANNEL_4, LL_DMA_MDATAALIGN_WORD);
/* USER CODE BEGIN ADC1_Init 1 */
/* USER CODE END ADC1_Init 1 */
/** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
*/
#define ADC_CHANNEL_CONF_RDY_TIMEOUT_MS ( 1U)
#if (USE_TIMEOUT == 1)
uint32_t Timeout ; /* Variable used for Timeout management */
#endif /* USE_TIMEOUT */
ADC_InitStruct.Clock = LL_ADC_CLOCK_SYNC_PCLK_DIV2;
ADC_InitStruct.Resolution = LL_ADC_RESOLUTION_12B;
ADC_InitStruct.DataAlignment = LL_ADC_DATA_ALIGN_RIGHT;
ADC_InitStruct.LowPowerMode = LL_ADC_LP_MODE_NONE;
LL_ADC_Init(ADC1, &ADC_InitStruct);
LL_ADC_REG_SetSequencerConfigurable(ADC1, LL_ADC_REG_SEQ_CONFIGURABLE);
/* Poll for ADC channel configuration ready */
#if (USE_TIMEOUT == 1)
Timeout = ADC_CHANNEL_CONF_RDY_TIMEOUT_MS;
#endif /* USE_TIMEOUT */
while (LL_ADC_IsActiveFlag_CCRDY(ADC1) == 0)
{
#if (USE_TIMEOUT == 1)
/* Check Systick counter flag to decrement the time-out value */
if (LL_SYSTICK_IsActiveCounterFlag())
{
if(Timeout-- == 0)
{
Error_Handler();
}
}
#endif /* USE_TIMEOUT */
}
/* Clear flag ADC channel configuration ready */
LL_ADC_ClearFlag_CCRDY(ADC1);
ADC_REG_InitStruct.TriggerSource = LL_ADC_REG_TRIG_SOFTWARE;
ADC_REG_InitStruct.SequencerLength = LL_ADC_REG_SEQ_SCAN_DISABLE;
ADC_REG_InitStruct.SequencerDiscont = LL_ADC_REG_SEQ_DISCONT_DISABLE;
ADC_REG_InitStruct.ContinuousMode = LL_ADC_REG_CONV_CONTINUOUS;
ADC_REG_InitStruct.DMATransfer = LL_ADC_REG_DMA_TRANSFER_UNLIMITED;
ADC_REG_InitStruct.Overrun = LL_ADC_REG_OVR_DATA_PRESERVED;
LL_ADC_REG_Init(ADC1, &ADC_REG_InitStruct);
LL_ADC_SetOverSamplingScope(ADC1, LL_ADC_OVS_DISABLE);
LL_ADC_SetTriggerFrequencyMode(ADC1, LL_ADC_CLOCK_FREQ_MODE_HIGH);
LL_ADC_SetSamplingTimeCommonChannels(ADC1, LL_ADC_SAMPLINGTIME_COMMON_1, LL_ADC_SAMPLINGTIME_1CYCLE_5);
LL_ADC_SetSamplingTimeCommonChannels(ADC1, LL_ADC_SAMPLINGTIME_COMMON_2, LL_ADC_SAMPLINGTIME_1CYCLE_5);
LL_ADC_DisableIT_EOC(ADC1);
LL_ADC_DisableIT_EOS(ADC1);
/* Enable ADC internal voltage regulator */
LL_ADC_EnableInternalRegulator(ADC1);
/* Delay for ADC internal voltage regulator stabilization. */
/* Compute number of CPU cycles to wait for, from delay in us. */
/* Note: Variable divided by 2 to compensate partially */
/* CPU processing cycles (depends on compilation optimization). */
/* Note: If system core clock frequency is below 200kHz, wait time */
/* is only a few CPU processing cycles. */
uint32_t wait_loop_index;
wait_loop_index = ((LL_ADC_DELAY_INTERNAL_REGUL_STAB_US * (SystemCoreClock / (100000 * 2))) / 10);
while(wait_loop_index != 0)
{
wait_loop_index--;
}
/** Configure Regular Channel
*/
LL_ADC_REG_SetSequencerRanks(ADC1, LL_ADC_REG_RANK_1, LL_ADC_CHANNEL_0);
LL_ADC_SetChannelSamplingTime(ADC1, LL_ADC_CHANNEL_0, LL_ADC_SAMPLINGTIME_COMMON_1);
/* USER CODE BEGIN ADC1_Init 2 */
/* USER CODE END ADC1_Init 2 */
}
static void MX_DMA_Init(void)
{
/* Init with LL driver */
/* DMA controller clock enable */
LL_AHB1_GRP1_EnableClock(LL_AHB1_GRP1_PERIPH_DMA1);
/* DMA interrupt init */
/* DMA1_Channel1_IRQn interrupt configuration */
NVIC_SetPriority(DMA1_Channel1_IRQn, 0);
NVIC_EnableIRQ(DMA1_Channel1_IRQn);
/* DMA1_Channel2_3_IRQn interrupt configuration */
NVIC_SetPriority(DMA1_Channel2_3_IRQn, 0);
NVIC_EnableIRQ(DMA1_Channel2_3_IRQn);
/* DMA1_Ch4_5_DMAMUX1_OVR_IRQn interrupt configuration */
NVIC_SetPriority(DMA1_Ch4_5_DMAMUX1_OVR_IRQn, 0);
NVIC_EnableIRQ(DMA1_Ch4_5_DMAMUX1_OVR_IRQn);
}
But how can I setup the variable where is the ADC result saved?
How can I start the ADC?
I tried to use ADC1->CR |= ADC_CR_ADSTART; and reading ADC1->DR; but only zeroes...
Thank you
My signal is current feedback from the triac controlled motor. When I switch on the triac, I start to find maximum/minimum (it is offseted to 3.3V/2) current peak to check overtorque.
So it is 100Hz half-period and ever half period I need to find maximum/minimum value.
1kOhm output impedance with + 100nF on the input is maybe acceptable (?)
Ok. 🙂
So need no cap here. (Or not more than 470pF , because 1nF max. load for the sensor.)
