Problem with STM32g070 ADC

[Olek1]

Hi,

I got a problem with STM32G070RBTx ADC configuration. I configured ADC in interrupt mode. After each conversion I change channel to measure different pin.

I got 9 pins to measure(PA0 - PA7 and PB12). With PINS on PORTA I got no problem but PB12 is problematic. According to datasheet it is connected to ADC1_IN16, but configuring Channel as ADC_CHANNEL_16 measure PA0 instead of PB12.

Here is the function to change channels in adc:

void config_ext_channel_ADC(uint32_t channel)
{
	  ADC_ChannelConfTypeDef sConfig = {0};
	  switch(channel)
	  {
	  case 0:
		  sConfig.Channel = ADC_CHANNEL_0;
		  break;
	  case 1:
		  sConfig.Channel = ADC_CHANNEL_1;
		  break;
	  case 2:
		  sConfig.Channel = ADC_CHANNEL_2;
		  break;
	  case 3:
		  sConfig.Channel = ADC_CHANNEL_3;
		  break;
	  case 4:
		  sConfig.Channel = ADC_CHANNEL_4;
		  break;
	  case 5:
		  sConfig.Channel = ADC_CHANNEL_5;
		  break;
	  case 6:
		  sConfig.Channel = ADC_CHANNEL_6;
		  break;
	  case 7:
		  sConfig.Channel = ADC_CHANNEL_7;
		  break;
	  case 8:
		  sConfig.Channel = ADC_CHANNEL_16;
		  break;
	  case 9:
		  sConfig.Channel = ADC_CHANNEL_TEMPSENSOR;
		  break;
	  case 10:
		  sConfig.Channel = ADC_CHANNEL_VBAT;
		  break;
	  case 11:
		  sConfig.Channel = ADC_CHANNEL_VREFINT;
		  break;
	  }
	  sConfig.Rank = ADC_REGULAR_RANK_1;
	  sConfig.SamplingTime = ADC_SAMPLINGTIME_COMMON_1;
	  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
	  {
	    Error_Handler();
	  }
}

What am I doing wrong?

Thanks in advance

[KoRba88]

I have the same issue in STM32G031K8.

It seems to be hardware related bug beacuse register values in HAL looks ok.

[Antoine Odonne]

Hello Olek,

May I ask you to share as well the mode selection of the ADC?

In ADC_CFGR1 register: Bit 21 CHSELRMOD: Mode selection of the ADC_CHSELR register

If set to '1', you use then the sequencer which can only manipulate Ch0 to CH14, selection is made on 4 bits, and an overflow of the bitfield would explain what you observe.

I am surprised that software would not spot this however.

Regards,

Antoine

[NGern]

I am running into the same issue with the inability to read ADC1_IN16. I see in the RM0454 Reference Manual it states "Only channel 0 to channel 14 can be selected in this sequence". So is there no way to select ADC1_IN16 and read its input level?