STM32H750 ADC1 DMA not working (Now working)

[GMiku.1]

Edit: This code is functional.

Hey Everyone,

For the last couple of days I was struggling with initializing the ADC1 with multiple Channels enabled and DMA on a STM32H750. I would be very thankful if someone could help me.

I used the CubeMX Code Generator, but since the DMA requires additional code I just took the generated code and put it in my custom Init function, so it is easier to read in this question. (If posting the generated code separately to my code would help I can do that too)

The Problem is that I can't get the DMA working. The data array wont change. (I also tried initializing the array with none zeros, in case the DMA writes 0 in the array but not even that)

The ADC is running fine. I can read the data register (DR) and it seems to get good readings.

//THIS CODE WORKS
volatile uint16_t data[256] = {0};
void ADC1_init()
{
	//CLOCKs
	LL_AHB1_GRP1_EnableClock(LL_AHB1_GRP1_PERIPH_DMA1);
	LL_AHB1_GRP1_EnableClock(LL_AHB1_GRP1_PERIPH_ADC12);
 
	LL_AHB4_GRP1_EnableClock(LL_AHB4_GRP1_PERIPH_GPIOA);
	LL_AHB4_GRP1_EnableClock(LL_AHB4_GRP1_PERIPH_GPIOB);
 
 
 
	LL_ADC_InitTypeDef ADC_InitStruct = { 0 };
	LL_ADC_REG_InitTypeDef ADC_REG_InitStruct = { 0 };
	LL_ADC_CommonInitTypeDef ADC_CommonInitStruct = { 0 };
	LL_GPIO_InitTypeDef GPIO_InitStruct = { 0 };
 
 
	//GPIO Init
	/**ADC1 GPIO Configuration
	 PA6   ------> ADC1_INP3
	 PA7   ------> ADC1_INP7
	 PB0   ------> ADC1_INP9
	 PB1   ------> ADC1_INP5
	 */
	GPIO_InitStruct.Pin = LL_GPIO_PIN_6 | LL_GPIO_PIN_7;
	GPIO_InitStruct.Mode = LL_GPIO_MODE_ANALOG;
	GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
	LL_GPIO_Init(GPIOA, &GPIO_InitStruct);
 
	GPIO_InitStruct.Pin = LL_GPIO_PIN_0 | LL_GPIO_PIN_1;
	GPIO_InitStruct.Mode = LL_GPIO_MODE_ANALOG;
	GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
	LL_GPIO_Init(GPIOB, &GPIO_InitStruct);
 
	//ADC
	ADC_InitStruct.Resolution = LL_ADC_RESOLUTION_16B;
	ADC_InitStruct.LowPowerMode = LL_ADC_LP_MODE_NONE;
	LL_ADC_Init(ADC1, &ADC_InitStruct);
	ADC_REG_InitStruct.TriggerSource = LL_ADC_REG_TRIG_SOFTWARE;
	ADC_REG_InitStruct.SequencerLength = LL_ADC_REG_SEQ_SCAN_ENABLE_4RANKS;
	ADC_REG_InitStruct.SequencerDiscont = DISABLE;
	ADC_REG_InitStruct.ContinuousMode = LL_ADC_REG_CONV_CONTINUOUS;
	ADC_REG_InitStruct.Overrun = LL_ADC_REG_OVR_DATA_OVERWRITTEN;
 
        //THIS WAS THE MISSING LINE 
	ADC_REG_InitStruct.DataTransferMode = LL_ADC_REG_DMA_TRANSFER_UNLIMITED;
 
 
	LL_ADC_REG_Init(ADC1, &ADC_REG_InitStruct);
 
	LL_ADC_SetOverSamplingScope(ADC1, LL_ADC_OVS_DISABLE);
 
	LL_ADC_DisableDeepPowerDown(ADC1);
	LL_ADC_EnableInternalRegulator(ADC1);
 
	/* Delay for ADC internal voltage regulator stabilization. */
	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--;}
 
 
	ADC_CommonInitStruct.CommonClock = LL_ADC_CLOCK_ASYNC_DIV16;
	ADC_CommonInitStruct.Multimode = LL_ADC_MULTI_INDEPENDENT;
	LL_ADC_CommonInit(__LL_ADC_COMMON_INSTANCE(ADC1), &ADC_CommonInitStruct);
 
	// Configure Regular Channel Rank 1 Channel 3
	LL_ADC_REG_SetSequencerRanks(ADC1, LL_ADC_REG_RANK_1, LL_ADC_CHANNEL_3);
	LL_ADC_SetChannelSamplingTime(ADC1, LL_ADC_CHANNEL_3, LL_ADC_SAMPLINGTIME_64CYCLES_5);
	LL_ADC_SetChannelSingleDiff(ADC1, LL_ADC_CHANNEL_3, LL_ADC_SINGLE_ENDED);
	LL_ADC_SetChannelPreSelection(ADC1, LL_ADC_CHANNEL_3);
 
	// Configure Regular Channel Rank 2 Channel 5
	LL_ADC_REG_SetSequencerRanks(ADC1, LL_ADC_REG_RANK_2, LL_ADC_CHANNEL_5);
	LL_ADC_SetChannelSamplingTime(ADC1, LL_ADC_CHANNEL_5, LL_ADC_SAMPLINGTIME_64CYCLES_5);
	LL_ADC_SetChannelSingleDiff(ADC1, LL_ADC_CHANNEL_5, LL_ADC_SINGLE_ENDED);
	LL_ADC_SetChannelPreSelection(ADC1, LL_ADC_CHANNEL_5);
 
	// Configure Regular Channel Rank 3 Channel 7
	LL_ADC_REG_SetSequencerRanks(ADC1, LL_ADC_REG_RANK_3, LL_ADC_CHANNEL_7);
	LL_ADC_SetChannelSamplingTime(ADC1, LL_ADC_CHANNEL_7, LL_ADC_SAMPLINGTIME_64CYCLES_5);
	LL_ADC_SetChannelSingleDiff(ADC1, LL_ADC_CHANNEL_7, LL_ADC_SINGLE_ENDED);
	LL_ADC_SetChannelPreSelection(ADC1, LL_ADC_CHANNEL_7);
 
	// Configure Regular Channel Rank 4 Channel 9
	LL_ADC_REG_SetSequencerRanks(ADC1, LL_ADC_REG_RANK_4, LL_ADC_CHANNEL_9);
	LL_ADC_SetChannelSamplingTime(ADC1, LL_ADC_CHANNEL_9, LL_ADC_SAMPLINGTIME_64CYCLES_5);
	LL_ADC_SetChannelSingleDiff(ADC1, LL_ADC_CHANNEL_9, LL_ADC_SINGLE_ENDED);
	LL_ADC_SetChannelPreSelection(ADC1, LL_ADC_CHANNEL_9);
 
	LL_ADC_Enable(ADC1);
 
	//DMA Init
	LL_DMA_SetDataTransferDirection(DMA1, LL_DMA_STREAM_0, LL_DMA_DIRECTION_PERIPH_TO_MEMORY);
 
	LL_DMA_SetPeriphIncMode(DMA1, LL_DMA_STREAM_0, LL_DMA_PERIPH_NOINCREMENT);
	LL_DMA_SetMemoryIncMode(DMA1, LL_DMA_STREAM_0, LL_DMA_MEMORY_INCREMENT);
 
	LL_DMA_SetPeriphSize(DMA1, LL_DMA_STREAM_0, LL_DMA_PDATAALIGN_HALFWORD);
	LL_DMA_SetMemorySize(DMA1, LL_DMA_STREAM_0, LL_DMA_MDATAALIGN_HALFWORD);
 
	LL_DMA_SetPeriphAddress(DMA1, LL_DMA_STREAM_0, LL_ADC_DMA_GetRegAddr(ADC1, LL_ADC_DMA_REG_REGULAR_DATA));
	LL_DMA_SetMemoryAddress(DMA1, LL_DMA_STREAM_0, (uint32_t) data);
	LL_DMA_SetDataLength(DMA1, LL_DMA_STREAM_0, 4);
 
	LL_DMA_SetPeriphRequest(DMA1, LL_DMA_STREAM_0, LL_DMAMUX1_REQ_ADC1);
 
	LL_DMA_SetStreamPriorityLevel(DMA1, LL_DMA_STREAM_0, LL_DMA_PRIORITY_HIGH);
	LL_DMA_SetMode(DMA1, LL_DMA_STREAM_0, LL_DMA_MODE_CIRCULAR);
	LL_DMA_DisableFifoMode(DMA1, LL_DMA_STREAM_0);
 
 
 
	LL_DMA_EnableStream(DMA1, LL_DMA_STREAM_0);
	LL_ADC_REG_StartConversion(ADC1);
 
}

I feel like I already did everything the reference manual demands, but obviously I am missing something.

Hopefully I gave enough information for anyone willing to help. In case I missed something I would be glad to provide it.

Thanks in advance

GM

[GMiku.1]

I finally got it working. I added the missing line to my questions. So hopefully I can ensure that other people don't have to cry themselves to sleep over this. 😅 😉