STM32F746 ADC multi channel with DMA problem!!!

[Mj.soleimani]

Hi

I tried to use ADC 2 Channel Scan Mode with DMA circular but it didn't work...and very strange point is when i init DAC with DMA , ADC works. |:

anybody knows why?

how i use ADC DMA without DAC initialize?

thanks for your help.

the ADC configurations :

 hadc1.Instance = ADC1;

 hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV2;

 hadc1.Init.Resolution = ADC_RESOLUTION_8B;

 hadc1.Init.ScanConvMode = ADC_SCAN_ENABLE;

 hadc1.Init.ContinuousConvMode = DISABLE;

 hadc1.Init.DiscontinuousConvMode = ENABLE;

 hadc1.Init.NbrOfDiscConversion = 1;

 hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_RISING;

 hadc1.Init.ExternalTrigConv = ADC_EXTERNALTRIGCONV_T2_TRGO;

 hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;

 hadc1.Init.NbrOfConversion = 2;

 hadc1.Init.DMAContinuousRequests = ENABLE;

 hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;

sConfig.Channel = ADC_CHANNEL_0;

 sConfig.Rank = ADC_REGULAR_RANK_1;

 sConfig.SamplingTime = ADC_SAMPLETIME_15CYCLES;

 sConfig.Channel = ADC_CHANNEL_6;

 sConfig.Rank = ADC_REGULAR_RANK_2;

[waclawek.jan]

Read out and compare the content of ADC and DMA (and TIM2) registers between the working and non-working cases.

JW

[TDK]

Obviously initializing the DAC is not required for the ADC DMA to function correctly. The answer must be simpler. Possibly a relevant DMA clock is initialized by the DAC initialization that is missed or incorrectly sequenced in the ADC initialization. The issue is not in the code you linked.

[Mj.soleimani]

Thank you for reply ,TDK.

the ADC,DAC and DMA initialized by CubeMx.

shouldn't i trust the cube??

[TDK]

If it’s not working, what do you think? Once cube generates code for you, it’s yours. You’re responsible for making sure it does what you want and debugging it when necessary.
You also give no details on what “didnt work�? means. The bug could easily be somewhere else.