Problem reading analog values from 3 different potentiometers on STM32 Nucleo-F446RE
I have been trying to use three pots as dials for a guitar effects pedal project. Their purpose is to simply read the voltage from 0 - 3.3V and with some scaling (to turn the raw readings into 0-100 values) in the code to store these 3 values inside an array of length 3 and also display them in my LCD. I have tried to use one pot per ADC (3 onboard) as well as different channels on the same ADC.
The weird thing is that it works as intended for the first 2 pots but if I add the 3rd one with the same ADC configurations it simply won't read. The value stays oscillating as if the pin was free or grounded.
I am using pins PA0, PA1, and PA2 for ADC1, ADC2, and ADC3 respectively. I am using 3.3V as the input for the pots. Please let me know if anything occurs to you or have had a similar issue in the past!
Here is my current code main and ADC init configs (all 3 are the same)
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int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_ADC1_Init();
MX_ADC2_Init();
MX_ADC3_Init();
/* USER CODE BEGIN 2 */
lcd16x2_init_4bits(URS_GPIO_Port, URS_Pin, UE_Pin, UD4_GPIO_Port, UD4_Pin, UD5_Pin, UD6_Pin, UD7_Pin);
lcd16x2_setCursor(0, 0);
lcd16x2_cursorShow(0);
HAL_Delay(500);
HAL_GPIO_TogglePin(LD2_GPIO_Port, LD2_Pin);
HAL_GPIO_TogglePin(LD2_GPIO_Port, LD2_Pin);
lcd16x2_clear();
lcd16x2_printf(" ADEPT");
HAL_Delay(1500);
lcd16x2_clear();
lcd16x2_setCursor(1, 0);
lcd16x2_printf(" FX System");
HAL_Delay(1500);
HAL_ADC_Start(&hadc1);
HAL_ADC_Start(&hadc2);
HAL_ADC_Start(&hadc3);
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
// Poll ADC1 for PotA
HAL_ADC_PollForConversion(&hadc1, 1000);
// Store value reading for PotA
potValues[0] = HAL_ADC_GetValue(&hadc1);
// scale value between 0 and 99
scaledValuePA = potValues[0] * 0.0247821;
if(scaledValuePA > 99) {
scaledValuePA = 99;
}
HAL_ADC_PollForConversion(&hadc2, 1000);
potValues[1] = HAL_ADC_GetValue(&hadc2);
scaledValuePB = potValues[1] * 0.0247821;
if(scaledValuePB > 99) {
scaledValuePB = 99;
}
HAL_ADC_PollForConversion(&hadc3, 1000);
potValues[2] = HAL_ADC_GetValue(&hadc3);
scaledValuePC = potValues[2] * 0.0247821;
if(scaledValuePC > 99) {
scaledValuePC = 99;
}
//Display Effect 1 Screen
lcd16x2_1stLine();
lcd16x2_printf(" Distortion");
lcd16x2_2ndLine();
//lcd16x2_printf(" A:00 B:00 C:00 ");
//lcd16x2_printf("Value1 = %.1f", 123.45))
lcd16x2_printf(" A:");
lcd16x2_printf("%d", scaledValuePA);
lcd16x2_printf(" B:");
lcd16x2_printf("%d", scaledValuePB);
lcd16x2_printf(" C:");
lcd16x2_printf("%d", scaledValuePC);
//lcd16x2_printf("%d", scaledValuePC);
//updateLCD();
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
-------------------------------------------------------------------------------
static void MX_ADC1_Init(void)
{
/* USER CODE BEGIN ADC1_Init 0 */
/* USER CODE END ADC1_Init 0 */
ADC_ChannelConfTypeDef sConfig = {0};
/* USER CODE BEGIN ADC1_Init 1 */
/* USER CODE END ADC1_Init 1 */
/** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
*/
hadc1.Instance = ADC1;
hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV4;
hadc1.Init.Resolution = ADC_RESOLUTION_12B;
hadc1.Init.ScanConvMode = DISABLE;
hadc1.Init.ContinuousConvMode = ENABLE;
hadc1.Init.DiscontinuousConvMode = DISABLE;
hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
hadc1.Init.NbrOfConversion = 1;
hadc1.Init.DMAContinuousRequests = DISABLE;
hadc1.Init.EOCSelection = ADC_EOC_SEQ_CONV;
if (HAL_ADC_Init(&hadc1) != HAL_OK)
{
Error_Handler();
}
/** Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
sConfig.Channel = ADC_CHANNEL_0;
sConfig.Rank = 1;
sConfig.SamplingTime = ADC_SAMPLETIME_144CYCLES;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN ADC1_Init 2 */
/* USER CODE END ADC1_Init 2 */
}
