/* USER CODE BEGIN Header */
/**
*******************************************************************************
* @file : main.c
* @brief : Main program body
*******************************************************************************
* @attention
*
* Copyright (c) 2025 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 "main.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
DAC_HandleTypeDef hdac;
/* USER CODE BEGIN PV */
const uint32_t OFFSET_DAC_VALUE = 4; // Adjust this based on your measurements (e.g., 1.2mV corresponds to 4 DAC steps)
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_DAC_Init(void);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
void DAC_Init(void) {
__HAL_RCC_DAC_CLK_ENABLE(); // Enable DAC clock
// Configure GPIO pin PA4 (DAC output)
GPIO_InitTypeDef GPIO_InitStruct = {0};
GPIO_InitStruct.Pin = GPIO_PIN_4;
GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
// Initialize DAC1
hdac.Instance = DAC;
HAL_DAC_Init(&hdac);
// Configure DAC channel 1 (PA4)
DAC_ChannelConfTypeDef sConfig = {0};
sConfig.DAC_Trigger = DAC_TRIGGER_NONE; // No trigger
sConfig.DAC_OutputBuffer = DAC_OUTPUTBUFFER_DISABLE; // Enable the output buffer
HAL_DAC_ConfigChannel(&hdac, &sConfig, DAC_CHANNEL_1);
// Start DAC output
HAL_DAC_Start(&hdac, DAC_CHANNEL_1);
}
void Set_DAC_Voltage(uint32_t dac_value)
{
// Ensure that dac_value is within the valid range (0 to 4095 for 12-bit resolution)
if (dac_value > 4095) dac_value = 4095;
HAL_DAC_SetValue(&hdac, DAC_CHANNEL_1, DAC_ALIGN_12B_R, dac_value);
}
void Delay_ms(uint32_t ms) {
HAL_Delay(ms); // Delay function using HAL library
}
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
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_DAC_Init();
/* USER CODE BEGIN 2 */
// Initialize DAC
DAC_Init();
while (1) {
// Set to 0V
Set_DAC_Voltage(0);
Delay_ms(2000); // Wait for 2 seconds
// Set to 3.3V
Set_DAC_Voltage(4095); // 3.3V corresponds to 4095 in 12-bit resolution
Delay_ms(2000); // Wait for 2 seconds
}
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Configure the main internal regulator output voltage
*/
__HAL_RCC_PWR_CLK_ENABLE();
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
RCC_OscInitStruct.PLL.PLLM = 8;
RCC_OscInitStruct.PLL.PLLN = 180;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
RCC_OscInitStruct.PLL.PLLQ = 2;
RCC_OscInitStruct.PLL.PLLR = 2;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Activate the Over-Drive mode
*/
if (HAL_PWREx_EnableOverDrive() != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB buses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
{
Error_Handler();
}
}
/**
* @brief DAC Initialization Function
* None
* @retval None
*/
static void MX_DAC_Init(void)
{
/* USER CODE BEGIN DAC_Init 0 */
/* USER CODE END DAC_Init 0 */
DAC_ChannelConfTypeDef sConfig = {0};
/* USER CODE BEGIN DAC_Init 1 */
/* USER CODE END DAC_Init 1 */
/** DAC Initialization
*/
hdac.Instance = DAC;
if (HAL_DAC_Init(&hdac) != HAL_OK)
{
Error_Handler();
}
/** DAC channel OUT1 config
*/
sConfig.DAC_Trigger = DAC_TRIGGER_NONE;
sConfig.DAC_OutputBuffer = DAC_OUTPUTBUFFER_ENABLE;
if (HAL_DAC_ConfigChannel(&hdac, &sConfig, DAC_CHANNEL_1) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN DAC_Init 2 */
/* USER CODE END DAC_Init 2 */
}
/**
* @brief GPIO Initialization Function
* None
* @retval None
*/
static void MX_GPIO_Init(void)
{
/* USER CODE BEGIN MX_GPIO_Init_1 */
/* USER CODE END MX_GPIO_Init_1 */
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOA_CLK_ENABLE();
/* USER CODE BEGIN MX_GPIO_Init_2 */
/* USER CODE END MX_GPIO_Init_2 */
}
/* USER CODE BEGIN 4 */
/* USER CODE END 4 */
/**
* @brief This function is executed in case of error occurrence.
* @retval None
*/
void Error_Handler(void)
{
/* USER CODE BEGIN Error_Handler_Debug */
/* User can add his own implementation to report the HAL error return state */
__disable_irq();
while (1)
{
}
/* USER CODE END Error_Handler_Debug */
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* file: pointer to the source file name
* line: assert_param error line source number
* @retval None
*/
void assert_failed(uint8_t *file, uint32_t line)
{
/* USER CODE BEGIN 6 */
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
Hello
I am using internal dac of f446 to get dc voltage from 0V to 3.3v but when I measure using multimeter im getting 1.2mv for 0v is it because im using internal dac or should i go with external dac like mcp4725 to get exact 0v as it is required for my application.
Like I want to generate dc voltage from 0v to 0.003v with stepsize of 0.0008(12bit resolution).
