Hi All,
I'm starting to get familiar with the STM32 Series of Microprocessors and I'm completing some exercises using a mixture of direct writting to peripherals and low level ST libraries using the CUBEMX to get familiar with the chips. I'm using the Nucleo -F072RB
At this point I stumbled across a challenge, regarding the ADC module. I don't seem to be able to read the values on chanel 2 and 3 (PA2 and PA3).
Using the code below I can read PB0 (Channel 8) just fine. I ave also tried to read te internal temperatre sensor and reference and they seem to work fine. Any ideas why the inputs at PORTA don't work?
My code to read the ADC is as follows:
...
ADC1->CHSELR = (ADC_CHSELR_CHSEL3);
while (1)
{
ADC1->SMPR = 7; // Sample Time
ADC1->CFGR1 &= ~ ADC_CFGR1_CONT; // Discontinuous mode
ADC1->CR |= ADC_CR_ADEN | ADC_CR_ADSTART;
while ((ADC1->ISR & ADC_ISR_EOC) == 0) /* Wait end of conversion */
{
ADC_Result[1] = ADC1->DR; /* Store the ADC conversion result */
}
}
This is my ADC init code:
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file adc.c
* @brief This file provides code for the configuration
* of the ADC instances.
******************************************************************************
* @attention
*
* Copyright (c) 2022 STMicroelectronics.
* All rights reserved.
*
* This software is licensed under terms that can be found in the LICENSE file
* in the root directory of this software component.
* If no LICENSE file comes with this software, it is provided AS-IS.
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "adc.h"
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */
/* ADC init function */
void MX_ADC_Init(void)
{
/* USER CODE BEGIN ADC_Init 0 */
/* USER CODE END ADC_Init 0 */
LL_ADC_InitTypeDef ADC_InitStruct = {0};
LL_ADC_REG_InitTypeDef ADC_REG_InitStruct = {0};
LL_GPIO_InitTypeDef GPIO_InitStruct = {0};
/* Peripheral clock enable */
LL_APB1_GRP2_EnableClock(LL_APB1_GRP2_PERIPH_ADC1);
LL_AHB1_GRP1_EnableClock(LL_AHB1_GRP1_PERIPH_GPIOA);
LL_AHB1_GRP1_EnableClock(LL_AHB1_GRP1_PERIPH_GPIOB);
/**ADC GPIO Configuration
PA2 ------> ADC_IN2
PA3 ------> ADC_IN3
*/
GPIO_InitStruct.Pin = LL_GPIO_PIN_2;
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_3;
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;
GPIO_InitStruct.Mode = LL_GPIO_MODE_ANALOG;
GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
LL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/* USER CODE BEGIN ADC_Init 1 */
/* USER CODE END ADC_Init 1 */
LL_ADC_REG_SetSequencerChAdd(ADC1, LL_ADC_CHANNEL_8);
/** Configure Regular Channel
*/
LL_ADC_REG_SetSequencerChAdd(ADC1, LL_ADC_CHANNEL_2);
/** Configure Regular Channel
*/
LL_ADC_REG_SetSequencerChAdd(ADC1, LL_ADC_CHANNEL_3);
/** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
*/
ADC_InitStruct.Clock = LL_ADC_CLOCK_ASYNC;
ADC_InitStruct.Resolution = LL_ADC_RESOLUTION_12B;
ADC_InitStruct.DataAlignment = LL_ADC_DATA_ALIGN_RIGHT;
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.SequencerDiscont = LL_ADC_REG_SEQ_DISCONT_DISABLE;
ADC_REG_InitStruct.ContinuousMode = LL_ADC_REG_CONV_SINGLE;
ADC_REG_InitStruct.DMATransfer = LL_ADC_REG_DMA_TRANSFER_LIMITED;
ADC_REG_InitStruct.Overrun = LL_ADC_REG_OVR_DATA_PRESERVED;
LL_ADC_REG_Init(ADC1, &ADC_REG_InitStruct);
LL_ADC_REG_SetSequencerScanDirection(ADC1, LL_ADC_REG_SEQ_SCAN_DIR_FORWARD);
LL_ADC_SetSamplingTimeCommonChannels(ADC1, LL_ADC_SAMPLINGTIME_1CYCLE_5);
/* USER CODE BEGIN ADC_Init 2 */
/* USER CODE END ADC_Init 2 */
}
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
