ADC1 in STM32H753 gets 0xFFFF as the digital value for HAL_ADC_Start & HAL_ADC_Start_IT & HAL_ADC_Start_DMA.

[Ofer]

I use ADC2 and ADC3 (with HAL_ADC_Start_DMA) with no problem, just having problem with ADC1. I'm using FREE-RTOS. STM32CUBEIDE.

[FBL]

Hello @Ofer​,

Could you please share your configuration? Pin configuration, DMA channel ...? IOC file if possible? 

Does conversions are performed sequentially or simultaneously?

Same issue observed without FreeRTOS?

[Ofer]

Hi dear Mr. Belaid

Attached the ioc file.

I use a simple polling conversion:

for( uint16_t sample_index = 0 ; sample_index < sample_number ; sample_index++ )

{

  HAL_ADC_Start(&hadc1);

HAL_ADC_PollForConversion(&hadc1, 1000);

modulation_feedback_samples[sample_index] = HAL_ADC_GetValue(&hadc1);

  HAL_ADC_Stop(&hadc1);

}

Have the same issue without FreeRTOS.

Thanks

[Ofer · Accepted solution]

Hi

The problem has been solved. The Vref was 1.5V (instead of 3.0V) so the signal was saturated.

Thanks anyway.