Hi,
​
I wrote a simplest program (below) to send sine wave data to PCM5102A (DAC) via I2S.
​However, I found only L-ch data is valid and R-ch has no data.
Analogue (DAC) output of L-ch is somewhat sine wave, but it is sometimes de-formed. And if I look it closer, I found some noise on the signal. (below captured screen shot)
I use HAL and STM32F401. And I2S settings are half-duplex master transmit (only).
Kindly enlighten me what is wrong with my program.
int main(void) {
HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_DMA_Init();
MX_I2S2_Init();
HAL_GPIO_WritePin(LD2_GPIO_Port, LD2_Pin, GPIO_PIN_SET); // LED Off
int16_t Wave_Data[n_data * 2];
for (int i = 0; i < n_data; i++) {
Wave_Data[i * 2] = (int16_t) (sin(2. * M_PI * 8. * i / 1000.) * 50) ; // L-ch
Wave_Data[i * 2 + 1] = (int16_t) (sin(2. * M_PI * 10. * i / 1000.) * 50) ; // R-ch
}
while (1) {
if (Wave_buf_empty == 1) {
while ((&hi2s2)->State != HAL_I2S_STATE_READY)
;
if (HAL_I2S_Transmit_DMA(&hi2s2, (uint16_t*) Wave_Data,
(uint16_t) n_data * 2) != HAL_OK) {
Error_Handler();
}
Wave_buf_empty = 0 ;
}
}
}
//////////// Call Back ///////////////
void HAL_I2S_TxCpltCallback(I2S_HandleTypeDef *hi2s) {
Wave_buf_empty = 1;
HAL_GPIO_TogglePin(LD2_GPIO_Port, LD2_Pin); // check if DMA is working
}Screen capture of USB scope.
​
​
1 ACCEPTED SOLUTION
Accepted Solutions
Dear JW and ALL,
Worked!!! :grinning_face: :grinning_face: :smiling_face_with_smiling_eyes:
I fount my code works well when I built the project from scratch with STM32CubeIDE.
Code itself is completely identical, however, there must have some glitch when I was working around the code for a week or two.
To share the result with the community, I put entire code and settings screen shots below. (How easy to use I2S with CubeMX!!)
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @attention
*
* <h2><center>© Copyright (c) 2020 STMicroelectronics.
* All rights reserved.</center></h2>
*
* This software component is licensed by ST under BSD 3-Clause license,
* the "License"; You may not use this file except in compliance with the
* License. You may obtain a copy of the License at:
* opensource.org/licenses/BSD-3-Clause
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include <string.h>
#include <stdio.h>
#include <math.h>
#define n_data 1000
/* 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 ---------------------------------------------------------*/
I2S_HandleTypeDef hi2s2;
DMA_HandleTypeDef hdma_spi2_tx;
/* USER CODE BEGIN PV */
uint8_t Wave_buf_empty = 1 ;
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_DMA_Init(void);
static void MX_I2S2_Init(void);
/* USER CODE BEGIN PFP */
void HAL_I2S_TxCpltCallback(I2S_HandleTypeDef *hi2s);
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
/* 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_DMA_Init();
MX_I2S2_Init();
/* USER CODE BEGIN 2 */
// With 48kHz sampling rate, L-ch will be 384Hz and R-ch will be 480Hz
int16_t Wave_Data[n_data * 2]; // n_data is defined as 1000
for (int i = 0; i < n_data; i++) {
Wave_Data[i * 2] = (int16_t) (sin(2. * M_PI * 8. * i / 1000.) * 500); // L-ch (x 500 is amplitude)
Wave_Data[i * 2 + 1] =
(int16_t) (sin(2. * M_PI * 10. * i / 1000.) * 500); // R-ch
printf("%d, %d\n", Wave_Data[i * 2], Wave_Data[i * 2 + 1]);
HAL_Delay(1);
}
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1) {
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
if (Wave_buf_empty == 1) {
while ((&hi2s2)->State != HAL_I2S_STATE_READY)
;
if (HAL_I2S_Transmit_DMA(&hi2s2, (uint16_t*) Wave_Data,
(uint16_t) n_data * 2) != HAL_OK) {
Error_Handler();
}
Wave_buf_empty = 0;
}
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {0};
/** Configure the main internal regulator output voltage
*/
__HAL_RCC_PWR_CLK_ENABLE();
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE2);
/** Initializes the CPU, AHB and APB busses clocks
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLM = 25;
RCC_OscInitStruct.PLL.PLLN = 168;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
RCC_OscInitStruct.PLL.PLLQ = 4;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB busses 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_DIV2;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
{
Error_Handler();
}
PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_I2S;
PeriphClkInitStruct.PLLI2S.PLLI2SN = 192;
PeriphClkInitStruct.PLLI2S.PLLI2SR = 2;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
{
Error_Handler();
}
}
/**
* @brief I2S2 Initialization Function
* @param None
* @retval None
*/
static void MX_I2S2_Init(void)
{
/* USER CODE BEGIN I2S2_Init 0 */
/* USER CODE END I2S2_Init 0 */
/* USER CODE BEGIN I2S2_Init 1 */
/* USER CODE END I2S2_Init 1 */
hi2s2.Instance = SPI2;
hi2s2.Init.Mode = I2S_MODE_MASTER_TX;
hi2s2.Init.Standard = I2S_STANDARD_PHILIPS;
hi2s2.Init.DataFormat = I2S_DATAFORMAT_16B;
hi2s2.Init.MCLKOutput = I2S_MCLKOUTPUT_DISABLE;
hi2s2.Init.AudioFreq = I2S_AUDIOFREQ_48K;
hi2s2.Init.CPOL = I2S_CPOL_LOW;
hi2s2.Init.ClockSource = I2S_CLOCK_PLL;
hi2s2.Init.FullDuplexMode = I2S_FULLDUPLEXMODE_DISABLE;
if (HAL_I2S_Init(&hi2s2) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN I2S2_Init 2 */
/* USER CODE END I2S2_Init 2 */
}
/**
* Enable DMA controller clock
*/
static void MX_DMA_Init(void)
{
/* DMA controller clock enable */
__HAL_RCC_DMA1_CLK_ENABLE();
/* DMA interrupt init */
/* DMA1_Stream4_IRQn interrupt configuration */
HAL_NVIC_SetPriority(DMA1_Stream4_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(DMA1_Stream4_IRQn);
}
/**
* @brief GPIO Initialization Function
* @param None
* @retval None
*/
static void MX_GPIO_Init(void)
{
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOC_CLK_ENABLE();
__HAL_RCC_GPIOH_CLK_ENABLE();
__HAL_RCC_GPIOB_CLK_ENABLE();
__HAL_RCC_GPIOA_CLK_ENABLE();
}
/* USER CODE BEGIN 4 */
void HAL_I2S_TxCpltCallback(I2S_HandleTypeDef *hi2s) {
Wave_buf_empty = 1 ;
}
/// enable "printf()" through SWO signal line ///
int _write(int file, char *ptr, int len)
{
int DataIdx;
for(DataIdx=0; DataIdx<len; DataIdx++)
{
ITM_SendChar(*ptr++);
}
return len;
}
/* 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 */
/* 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.
* @param file: pointer to the source file name
* @param 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,
tex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
Clock configuration
I2S configuration
DMA configuration
Output
