ADC channel numbers incorrect on datasheet STM32U031R8T6

[KSB]

Hi,

I am just trying to run adc in discontonous mode to measure some voltate from two resistor divider connected on channel 6 (PA1) and channel 7 (PA2) and also Vref from internal channel 12 as per datasheet. see below screenshot from DS14581- Rev2

 

below is the code

RCC->APBENR2|=RCC_APBENR2_ADCEN; //enable adc clock

ADC1_COMMON->CCR=ADC_CCR_VREFEN; //

ADC1->CFGR2|=(1<<ADC_CFGR2_CKMODE_Pos); clock divide by 2

ADC1->CFGR1|=ADC_CFGR1_DISCEN; // discontinuos mode

ADC1->SMPR=0x05; //sampling time setting

ADC1->CR=ADC_CR_ADCAL|ADC_CR_ADVREGEN; // start adc calibration

while((ADC1->CR)&(ADC_CR_ADCAL)) // wait while adc calibraion is not complete

{};

ADC1->CR=ADC_CR_ADEN; // ADC enable

ADC1->CHSELR=ADC_CHSELR_CHSEL6|ADC_CHSELR_CHSEL7|ADC_CHSELR_CHSEL12;// select channels to be converted

ADC1->CR=0x05; //ADC enable and start conversion.

uint16_t adc_data=ADC1->DR;

 

I have tested that when I choose below configuration for channels . I get the desired results.

ADC1->CHSELR=ADC_CHSELR_CHSEL5|ADC_CHSELR_CHSEL6|ADC_CHSELR_CHSEL11;

So that clearly means that  ADC channel 5 is connected to PA1, ADC channel 6 is connected to PA2 and VREFINT is ADC channel 11 in contrast to what is mentioned in the reference manual RM0503 Rev2. and the datasheet of the product.

 

Please confirm.

 

[KDJEM.1]

Hello @KSB ,

 

First, I apologize for my late reply.

Thank you for bringing this issue to our attention.

I confirm this is a documentation issue. In the DS14581- Rev2, ADC channels numbering starts by mistake from ADC_IN1 instead of ADC_IN0. 

I reported this typo internally

Internal ticket number: 182169 (This is an internal tracking number and is not accessible or usable by customers).

 

Thank you.

Kaouthar

[Viktor POHORELY]

First, really sorry about the difficulties due to documentation misalignment.

Documents are ongoing update to have it fixed.