/** ****************************************************************************** * @file stm324xg_eval_audio.c * @author MCD Application Team * @brief This file provides the Audio driver for the STM324xG-EVAL evaluation * board. ****************************************************************************** * @attention * * Copyright (c) 2017 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 NOTES How To use this driver: ----------------------- + This driver supports STM32F4xx devices on STM324xG-EVAL Evaluation board. + Call the function BSP_AUDIO_OUT_Init( OutputDevice: physical output mode (OUTPUT_DEVICE_SPEAKER, OUTPUT_DEVICE_HEADPHONE, OUTPUT_DEVICE_AUTO or OUTPUT_DEVICE_BOTH) Volume: initial volume to be set (0 is min (mute), 100 is max (100%) AudioFreq: Audio frequency in Hz (8000, 16000, 22500, 32000 ...) this parameter is relative to the audio file/stream type. ) This function configures all the hardware required for the audio application (codec, I2C, I2S, GPIOs, DMA and interrupt if needed). This function returns 0 if configuration is OK. If the returned value is different from 0 or the function is stuck then the communication with the codec or the IOExpander has failed (try to un-plug the power or reset device in this case). - OUTPUT_DEVICE_SPEAKER: only speaker will be set as output for the audio stream. - OUTPUT_DEVICE_HEADPHONE: only headphones will be set as output for the audio stream. - OUTPUT_DEVICE_AUTO: Selection of output device is made through external switch (implemented into the audio jack on the evaluation board). When the Headphone is connected it is used as output. When the headphone is disconnected from the audio jack, the output is automatically switched to Speaker. - OUTPUT_DEVICE_BOTH: both Speaker and Headphone are used as outputs for the audio stream at the same time. + Call the function BSP_AUDIO_OUT_Play( pBuffer: pointer to the audio data file address Size: size of the buffer to be sent in Bytes ) to start playing (for the first time) from the audio file/stream. + Call the function BSP_AUDIO_OUT_Pause() to pause playing + Call the function BSP_AUDIO_OUT_Resume() to resume playing. Note. After calling BSP_AUDIO_OUT_Pause() function for pause, only BSP_AUDIO_OUT_Resume() should be called for resume (it is not allowed to call BSP_AUDIO_OUT_Play() in this case). Note. This function should be called only when the audio file is played or paused (not stopped). + For each mode, you may need to implement the relative callback functions into your code. The Callback functions are named AUDIO_OUT_XXX_CallBack() and only their prototypes are declared in the stm324xg_eval_audio.h file. (refer to the example for more details on the callbacks implementations) + To Stop playing, to modify the volume level or to mute, use the functions BSP_AUDIO_OUT_Stop(), BSP_AUDIO_OUT_SetVolume(), AUDIO_OUT_SetFrequency() BSP_AUDIO_OUT_SetOutputMode and BSP_AUDIO_OUT_SetMute(). + The driver API and the callback functions are at the end of the stm324xg_eval_audio.h file. Driver architecture: ------------------- + This driver provide the High Audio Layer: consists of the function API exported in the stm324xg_eval_audio.h file (BSP_AUDIO_OUT_Init(), BSP_AUDIO_OUT_Play() ...) + This driver provide also the Media Access Layer (MAL): which consists of functions allowing to access the media containing/ providing the audio file/stream. These functions are also included as local functions into the stm324xg_eval_audio_codec.c file (I2Sx_MspInit() and I2Sx_Init()) Known Limitations: ------------------- 1- When using the Speaker, if the audio file quality is not high enough, the speaker output may produce high and uncomfortable noise level. To avoid this issue, to use speaker output properly, try to increase audio file sampling rate (typically higher than 48KHz). This operation will lead to larger file size. 2- Communication with the audio codec (through I2C) may be corrupted if it is interrupted by some user interrupt routines (in this case, interrupts could be disabled just before the start of communication then re-enabled when it is over). Note that this communication is only done at the configuration phase (BSP_AUDIO_OUT_Init() or BSP_AUDIO_OUT_Stop()) and when Volume control modification is performed (BSP_AUDIO_OUT_SetVolume() or AUDIO_OUT_Mute() or BSP_AUDIO_OUT_SetOutputMode()). When the audio data is played, no communication is required with the audio codec. 3- Parsing of audio file is not implemented (in order to determine audio file properties: Mono/Stereo, Data size, File size, Audio Frequency, Audio Data header size ...). The configuration is fixed for the given audio file. 4- Supports only Stereo audio streaming. To play mono audio streams, each data should be sent twice on the I2S or should be duplicated on the source buffer. Or convert the stream in stereo before playing. 5- Supports only 16-bits audio data size. ==============================================================================*//* ... */ /* Includes ------------------------------------------------------------------*/ #include "stm324xg_eval_audio.h" #include "stm324xg_eval_io.h" /* IOExpander driver is included in order to allow CS43L22 codec reset pin management on the evaluation board *//* ... */ /** @addtogroup BSP * @{ *//* ... */ /** @addtogroup STM324xG_EVAL * @{ *//* ... */ /** @defgroup STM324xG_EVAL_AUDIO STM324xG EVAL AUDIO * @brief This file includes the low layer audio driver available on STM324xG-EVAL * evaluation board. * @{ *//* ... */ /** @defgroup STM324xG_EVAL_AUDIO_Private_Defines STM324xG EVAL AUDIO Private Defines * @{ *//* ... */ /* These PLL parameters are valid when the f(VCO clock) = 1Mhz */ const uint32_t I2SFreq[8] = {8000, 11025, 16000, 22050, 32000, 44100, 48000, 96000}; const uint32_t I2SPLLN[8] = {256, 429, 213, 429, 426, 271, 258, 344}; const uint32_t I2SPLLR[8] = {5, 4, 4, 4, 4, 6, 3, 1}; /** * @} *//* ... */ /** @defgroup STM324xG_EVAL_AUDIO_Private_Variables STM324xG EVAL AUDIO Private Variables * @{ *//* ... */ AUDIO_DrvTypeDef *audio_drv; I2S_HandleTypeDef haudio_i2s; /** * @} *//* ... */ /** @defgroup STM324xG_EVAL_AUDIO_Private_Function_Prototypes STM324xG EVAL AUDIO Private Function Prototypes * @{ *//* ... */ static void I2Sx_Init(uint32_t AudioFreq); static void I2Sx_DeInit(void); static void CODEC_Reset(void); /** * @} *//* ... */ /** @defgroup STM324xG_EVAL_AUDIO_Private_Functions STM324xG EVAL AUDIO Private Functions * @{ *//* ... */ /** * @brief Configures the audio peripherals. * @param OutputDevice: OUTPUT_DEVICE_SPEAKER, OUTPUT_DEVICE_HEADPHONE, * OUTPUT_DEVICE_BOTH or OUTPUT_DEVICE_AUTO . * @param Volume: Initial volume level (from 0 (Mute) to 100 (Max)) * @param AudioFreq: Audio frequency used to play the audio stream. * @note This function configure also that the I2S PLL input clock. * @retval 0 if correct communication, else wrong communication *//* ... */ uint8_t BSP_AUDIO_OUT_Init(uint16_t OutputDevice, uint8_t Volume, uint32_t AudioFreq) { uint8_t ret = AUDIO_ERROR; /* Disable I2S */ I2Sx_DeInit(); /* Configure PLL clock depending on AudioFreq */ BSP_AUDIO_OUT_ClockConfig(&haudio_i2s, AudioFreq, NULL); /* I2S data transfer preparation: Prepare the Media to be used for the audio transfer from memory to I2S peripheral *//* ... */ haudio_i2s.Instance = AUDIO_I2Sx; if(HAL_I2S_GetState(&haudio_i2s) == HAL_I2S_STATE_RESET) { /* Init the I2S MSP: this __weak function can be redefined by the application*/ BSP_AUDIO_OUT_MspInit(&haudio_i2s, NULL); }if (HAL_I2S_GetState(&haudio_i2s) == HAL_I2S_STATE_RESET) { ... } /* Configure the I2S peripheral */ I2Sx_Init(AudioFreq); /* Reset the Codec Registers */ CODEC_Reset(); if(((cs43l22_drv.ReadID(AUDIO_I2C_ADDRESS)) & CS43L22_ID_MASK) == CS43L22_ID) { /* Initialize the audio driver structure */ audio_drv = &cs43l22_drv; ret = AUDIO_OK; }if (((cs43l22_drv.ReadID(AUDIO_I2C_ADDRESS)) & CS43L22_ID_MASK) == CS43L22_ID) { ... } else { ret = AUDIO_ERROR; }else { ... } if(ret == AUDIO_OK) { audio_drv->Init(AUDIO_I2C_ADDRESS, OutputDevice, Volume, AudioFreq); }if (ret == AUDIO_OK) { ... } return ret; }{ ... } /** * @brief De-initialize the audio peripherals. * @retval None *//* ... */ void BSP_AUDIO_OUT_DeInit(void) { I2Sx_DeInit(); /* DeInit the I2S MSP : this __weak function can be rewritten by the application */ BSP_AUDIO_OUT_MspDeInit(&haudio_i2s, NULL); }{ ... } /** * @brief Starts playing audio stream from a data buffer for a determined size. * @param pBuffer: Pointer to the buffer * @param Size: Number of audio data BYTES. * @retval AUDIO_OK if correct communication, else wrong communication *//* ... */ uint8_t BSP_AUDIO_OUT_Play(uint16_t* pBuffer, uint32_t Size) { /* Call the audio Codec Play function */ if(audio_drv->Play(AUDIO_I2C_ADDRESS, pBuffer, Size) != 0) { return AUDIO_ERROR; }if (audio_drv->Play(AUDIO_I2C_ADDRESS, pBuffer, Size) != 0) { ... } else { /* Update the Media layer and enable it for play */ HAL_I2S_Transmit_DMA(&haudio_i2s, pBuffer, DMA_MAX(Size/AUDIODATA_SIZE)); return AUDIO_OK; }else { ... } }{ ... } /** * @brief Sends n-Bytes on the I2S interface. * @param pData: Pointer to data address * @param Size: Number of data to be written. *//* ... */ void BSP_AUDIO_OUT_ChangeBuffer(uint16_t *pData, uint16_t Size) { HAL_I2S_Transmit_DMA(&haudio_i2s, pData, Size); }{ ... } /** * @brief Pauses the audio file stream. * In case of using DMA, the DMA Pause feature is used. * WARNING: When calling BSP_AUDIO_OUT_Pause() function for pause, only * BSP_AUDIO_OUT_Resume() function should be called for resume (use of BSP_AUDIO_OUT_Play() * function for resume could lead to unexpected behavior). * @retval AUDIO_OK if correct communication, else wrong communication *//* ... */ uint8_t BSP_AUDIO_OUT_Pause(void) { /* Call the Audio Codec Pause/Resume function */ if(audio_drv->Pause(AUDIO_I2C_ADDRESS) != 0) { return AUDIO_ERROR; }if (audio_drv->Pause(AUDIO_I2C_ADDRESS) != 0) { ... } else { /* Call the Media layer pause function */ HAL_I2S_DMAPause(&haudio_i2s); /* Return AUDIO_OK when all operations are correctly done */ return AUDIO_OK; }else { ... } }{ ... } /** * @brief Resumes the audio file stream. * WARNING: When calling BSP_AUDIO_OUT_Pause() function for pause, only * BSP_AUDIO_OUT_Resume() function should be called for resume (use of BSP_AUDIO_OUT_Play() * function for resume could lead to unexpected behavior). * @retval AUDIO_OK if correct communication, else wrong communication *//* ... */ uint8_t BSP_AUDIO_OUT_Resume(void) { /* Call the Audio Codec Pause/Resume function */ if(audio_drv->Resume(AUDIO_I2C_ADDRESS) != 0) { return AUDIO_ERROR; }if (audio_drv->Resume(AUDIO_I2C_ADDRESS) != 0) { ... } else { /* Call the Media layer pause/resume function */ HAL_I2S_DMAResume(&haudio_i2s); /* Return AUDIO_OK when all operations are correctly done */ return AUDIO_OK; }else { ... } }{ ... } /** * @brief Stops audio playing and Power down the Audio Codec. * @param Option: could be one of the following parameters * - CODEC_PDWN_SW: for software power off (by writing registers). * Then no need to reconfigure the Codec after power on. * - CODEC_PDWN_HW: completely shut down the codec (physically). * Then need to reconfigure the Codec after power on. * @retval AUDIO_OK if correct communication, else wrong communication *//* ... */ uint8_t BSP_AUDIO_OUT_Stop(uint32_t Option) { /* Call the Media layer stop function */ HAL_I2S_DMAStop(&haudio_i2s); /* Call Audio Codec Stop function */ if(audio_drv->Stop(AUDIO_I2C_ADDRESS, Option) != 0) { return AUDIO_ERROR; }if (audio_drv->Stop(AUDIO_I2C_ADDRESS, Option) != 0) { ... } else { if(Option == CODEC_PDWN_HW) { /* Wait at least 1ms */ HAL_Delay(1); /* Reset the pin */ BSP_IO_WritePin(AUDIO_RESET_PIN, RESET); }if (Option == CODEC_PDWN_HW) { ... } /* Return AUDIO_OK when all operations are correctly done */ return AUDIO_OK; }else { ... } }{ ... } /** * @brief Controls the current audio volume level. * @param Volume: Volume level to be set in percentage from 0% to 100% (0 for * Mute and 100 for Max volume level). * @retval AUDIO_OK if correct communication, else wrong communication *//* ... */ uint8_t BSP_AUDIO_OUT_SetVolume(uint8_t Volume) { /* Call the codec volume control function with converted volume value */ if(audio_drv->SetVolume(AUDIO_I2C_ADDRESS, Volume) != 0) { return AUDIO_ERROR; }if (audio_drv->SetVolume(AUDIO_I2C_ADDRESS, Volume) != 0) { ... } else { /* Return AUDIO_OK when all operations are correctly done */ return AUDIO_OK; }else { ... } }{ ... } /** * @brief Enables or disables the MUTE mode by software * @param Cmd: could be AUDIO_MUTE_ON to mute sound or AUDIO_MUTE_OFF to * unmute the codec and restore previous volume level. * @retval AUDIO_OK if correct communication, else wrong communication *//* ... */ uint8_t BSP_AUDIO_OUT_SetMute(uint32_t Cmd) { /* Call the Codec Mute function */ if(audio_drv->SetMute(AUDIO_I2C_ADDRESS, Cmd) != 0) { return AUDIO_ERROR; }if (audio_drv->SetMute(AUDIO_I2C_ADDRESS, Cmd) != 0) { ... } else { /* Return AUDIO_OK when all operations are correctly done */ return AUDIO_OK; }else { ... } }{ ... } /** * @brief Switch dynamically (while audio file is played) the output target * (speaker or headphone). * @note This function modifies a global variable of the audio codec driver: OutputDev. * @param Output: specifies the audio output target: OUTPUT_DEVICE_SPEAKER, * OUTPUT_DEVICE_HEADPHONE, OUTPUT_DEVICE_BOTH or OUTPUT_DEVICE_AUTO * @retval AUDIO_OK if correct communication, else wrong communication *//* ... */ uint8_t BSP_AUDIO_OUT_SetOutputMode(uint8_t Output) { /* Call the Codec output Device function */ if(audio_drv->SetOutputMode(AUDIO_I2C_ADDRESS, Output) != 0) { return AUDIO_ERROR; }if (audio_drv->SetOutputMode(AUDIO_I2C_ADDRESS, Output) != 0) { ... } else { /* Return AUDIO_OK when all operations are correctly done */ return AUDIO_OK; }else { ... } }{ ... } /** * @brief Updates the audio frequency. * @param AudioFreq: Audio frequency used to play the audio stream. * @retval AUDIO_OK if correct communication, else wrong communication *//* ... */ void BSP_AUDIO_OUT_SetFrequency(uint32_t AudioFreq) { /* Configure PLL clock depending on AudioFreq */ BSP_AUDIO_OUT_ClockConfig(&haudio_i2s, AudioFreq, NULL); /* Update the I2S audio frequency configuration */ I2Sx_Init(AudioFreq); }{ ... } /** * @brief Clock Config. * @param hi2s: might be required to set audio peripheral predivider if any. * @param AudioFreq: Audio frequency used to play the audio stream. * @param Params * @note This API is called by BSP_AUDIO_OUT_Init() and BSP_AUDIO_OUT_SetFrequency() * Being __weak it can be overwritten by the application * @retval None *//* ... */ __weak void BSP_AUDIO_OUT_ClockConfig(I2S_HandleTypeDef *hi2s, uint32_t AudioFreq, void *Params) { RCC_PeriphCLKInitTypeDef RCC_ExCLKInitStruct; uint8_t index = 0, freqindex = 0xFF; for(index = 0; index < 8; index++) { if(I2SFreq[index] == AudioFreq) { freqindex = index; }if (I2SFreq[index] == AudioFreq) { ... } }for (index = 0; index < 8; index++) { ... } HAL_RCCEx_GetPeriphCLKConfig(&RCC_ExCLKInitStruct); if(freqindex != 0xFF) { /* I2S clock config PLLI2S_VCO = f(VCO clock) = f(PLLI2S clock input) � (PLLI2SN/PLLM) I2SCLK = f(PLLI2S clock output) = f(VCO clock) / PLLI2SR *//* ... */ RCC_ExCLKInitStruct.PeriphClockSelection = RCC_PERIPHCLK_I2S; RCC_ExCLKInitStruct.PLLI2S.PLLI2SN = I2SPLLN[freqindex]; RCC_ExCLKInitStruct.PLLI2S.PLLI2SR = I2SPLLR[freqindex]; HAL_RCCEx_PeriphCLKConfig(&RCC_ExCLKInitStruct); }if (freqindex != 0xFF) { ... } else /* Default PLL I2S configuration */ { /* I2S clock config PLLI2S_VCO = f(VCO clock) = f(PLLI2S clock input) � (PLLI2SN/PLLM) I2SCLK = f(PLLI2S clock output) = f(VCO clock) / PLLI2SR *//* ... */ RCC_ExCLKInitStruct.PeriphClockSelection = RCC_PERIPHCLK_I2S; RCC_ExCLKInitStruct.PLLI2S.PLLI2SN = 258; RCC_ExCLKInitStruct.PLLI2S.PLLI2SR = 3; HAL_RCCEx_PeriphCLKConfig(&RCC_ExCLKInitStruct); }else { ... } }{ ... } /** * @brief Initializes BSP_AUDIO_OUT MSP. * @param hi2s: I2S handle * @param Params *//* ... */ __weak void BSP_AUDIO_OUT_MspInit(I2S_HandleTypeDef *hi2s, void *Params) { static DMA_HandleTypeDef hdma_i2sTx; GPIO_InitTypeDef GPIO_InitStruct; /* Enable I2S clock */ AUDIO_I2Sx_CLK_ENABLE(); /* Enable SCK, SD and WS GPIO clock */ AUDIO_I2Sx_SCK_SD_WS_CLK_ENABLE(); /* CODEC_I2S pins configuration: WS, SCK and SD pins */ GPIO_InitStruct.Pin = AUDIO_I2Sx_WS_PIN | AUDIO_I2Sx_SCK_PIN | AUDIO_I2Sx_SD_PIN; GPIO_InitStruct.Mode = GPIO_MODE_AF_PP; GPIO_InitStruct.Pull = GPIO_NOPULL; GPIO_InitStruct.Speed = GPIO_SPEED_FAST; GPIO_InitStruct.Alternate = AUDIO_I2Sx_SCK_SD_WS_AF; HAL_GPIO_Init(AUDIO_I2Sx_SCK_SD_WS_GPIO_PORT, &GPIO_InitStruct); /* Enable MCK GPIO clock */ AUDIO_I2Sx_MCK_CLK_ENABLE(); /* CODEC_I2S pins configuration: MCK pin */ GPIO_InitStruct.Pin = AUDIO_I2Sx_MCK_PIN; HAL_GPIO_Init(AUDIO_I2Sx_MCK_GPIO_PORT, &GPIO_InitStruct); /* Enable the DMA clock */ AUDIO_I2Sx_DMAx_CLK_ENABLE(); if(hi2s->Instance == AUDIO_I2Sx) { /* Configure the hdma_i2sTx handle parameters */ hdma_i2sTx.Init.Channel = AUDIO_I2Sx_DMAx_CHANNEL; hdma_i2sTx.Init.Direction = DMA_MEMORY_TO_PERIPH; hdma_i2sTx.Init.PeriphInc = DMA_PINC_DISABLE; hdma_i2sTx.Init.MemInc = DMA_MINC_ENABLE; hdma_i2sTx.Init.PeriphDataAlignment = AUDIO_I2Sx_DMAx_PERIPH_DATA_SIZE; hdma_i2sTx.Init.MemDataAlignment = AUDIO_I2Sx_DMAx_MEM_DATA_SIZE; hdma_i2sTx.Init.Mode = DMA_NORMAL; hdma_i2sTx.Init.Priority = DMA_PRIORITY_HIGH; hdma_i2sTx.Init.FIFOMode = DMA_FIFOMODE_ENABLE; hdma_i2sTx.Init.FIFOThreshold = DMA_FIFO_THRESHOLD_FULL; hdma_i2sTx.Init.MemBurst = DMA_MBURST_SINGLE; hdma_i2sTx.Init.PeriphBurst = DMA_PBURST_SINGLE; hdma_i2sTx.Instance = AUDIO_I2Sx_DMAx_STREAM; /* Associate the DMA handle */ __HAL_LINKDMA(hi2s, hdmatx, hdma_i2sTx); /* Deinitialize the Stream for new transfer */ HAL_DMA_DeInit(&hdma_i2sTx); /* Configure the DMA Stream */ HAL_DMA_Init(&hdma_i2sTx); }if (hi2s->Instance == AUDIO_I2Sx) { ... } /* I2S DMA IRQ Channel configuration */ HAL_NVIC_SetPriority(AUDIO_I2Sx_DMAx_IRQ, AUDIO_IRQ_PREPRIO, 0); HAL_NVIC_EnableIRQ(AUDIO_I2Sx_DMAx_IRQ); }{ ... } /** * @brief De-Initializes BSP_AUDIO_OUT MSP. * @param hi2s: I2S handle * @param Params *//* ... */ __weak void BSP_AUDIO_OUT_MspDeInit(I2S_HandleTypeDef *hi2s, void *Params) { GPIO_InitTypeDef GPIO_InitStruct; /* Disable I2S clock */ AUDIO_I2Sx_CLK_DISABLE(); /* CODEC_I2S pins configuration: WS, SCK and SD pins */ GPIO_InitStruct.Pin = AUDIO_I2Sx_WS_PIN | AUDIO_I2Sx_SCK_PIN | AUDIO_I2Sx_SD_PIN; HAL_GPIO_DeInit(AUDIO_I2Sx_SCK_SD_WS_GPIO_PORT, GPIO_InitStruct.Pin); /* CODEC_I2S pins configuration: MCK pin */ GPIO_InitStruct.Pin = AUDIO_I2Sx_MCK_PIN; HAL_GPIO_DeInit(AUDIO_I2Sx_MCK_GPIO_PORT, GPIO_InitStruct.Pin); }{ ... } /** * @brief Tx Transfer completed callbacks * @param hi2s: I2S handle *//* ... */ void HAL_I2S_TxCpltCallback(I2S_HandleTypeDef *hi2s) { /* Manage the remaining file size and new address offset: This function should be coded by user (its prototype is already declared in stm324xg_eval_audio.h) *//* ... */ BSP_AUDIO_OUT_TransferComplete_CallBack(); }{ ... } /** * @brief Tx Transfer Half completed callbacks * @param hi2s: I2S handle *//* ... */ void HAL_I2S_TxHalfCpltCallback(I2S_HandleTypeDef *hi2s) { /* Manage the remaining file size and new address offset: This function should be coded by user (its prototype is already declared in stm324xg_eval_audio.h) *//* ... */ BSP_AUDIO_OUT_HalfTransfer_CallBack(); }{ ... } /** * @brief I2S error callbacks. * @param hi2s: I2S handle *//* ... */ void HAL_I2S_ErrorCallback(I2S_HandleTypeDef *hi2s) { BSP_AUDIO_OUT_Error_CallBack(); }{ ... } /** * @brief Manages the DMA full Transfer complete event. *//* ... */ __weak void BSP_AUDIO_OUT_TransferComplete_CallBack(void) { }{ ... } /** * @brief Manages the DMA Half Transfer complete event. *//* ... */ __weak void BSP_AUDIO_OUT_HalfTransfer_CallBack(void) { }{ ... } /** * @brief Manages the DMA FIFO error event. *//* ... */ __weak void BSP_AUDIO_OUT_Error_CallBack(void) { }{ ... } /******************************************************************************* Static Functions *******************************************************************************//* ... */ /** * @brief Initializes the Audio Codec audio interface (I2S). * @param AudioFreq: Audio frequency to be configured for the I2S peripheral. *//* ... */ static void I2Sx_Init(uint32_t AudioFreq) { /* Initialize the haudio_i2s Instance parameter */ haudio_i2s.Instance = AUDIO_I2Sx; /* Disable I2S block */ __HAL_I2S_DISABLE(&haudio_i2s); haudio_i2s.Init.Mode = I2S_MODE_MASTER_TX; haudio_i2s.Init.Standard = I2S_STANDARD; haudio_i2s.Init.DataFormat = I2S_DATAFORMAT_16B; haudio_i2s.Init.AudioFreq = AudioFreq; haudio_i2s.Init.CPOL = I2S_CPOL_LOW; haudio_i2s.Init.MCLKOutput = I2S_MCLKOUTPUT_ENABLE; /* Init the I2S */ HAL_I2S_Init(&haudio_i2s); }{ ... } /** * @brief Deinitialize the Audio Codec audio interface (I2S). *//* ... */ static void I2Sx_DeInit(void) { /* Initialize the haudio_i2s Instance parameter */ haudio_i2s.Instance = AUDIO_I2Sx; /* Disable I2S peripheral */ __HAL_I2S_DISABLE(&haudio_i2s); HAL_I2S_DeInit(&haudio_i2s); }{ ... } /** * @brief Resets the audio codec. It restores the default configuration of the * codec (this function shall be called before initializing the codec). * @note This function calls an external driver function: The IO Expander driver. *//* ... */ static void CODEC_Reset(void) { /* Configure the IO Expander (to use the Codec Reset pin mapped on the IOExpander) */ BSP_IO_Init(); BSP_IO_ConfigPin(AUDIO_RESET_PIN, IO_MODE_OUTPUT); /* Power Down the codec */ BSP_IO_WritePin(AUDIO_RESET_PIN, RESET); /* Wait for a delay to insure registers erasing */ HAL_Delay(CODEC_RESET_DELAY); /* Power on the codec */ BSP_IO_WritePin(AUDIO_RESET_PIN, SET); /* Wait for a delay to insure registers erasing */ HAL_Delay(CODEC_RESET_DELAY); }{ ... } /** * @} *//* ... */ /** * @} *//* ... */ /** * @} *//* ... */ /** * @} *//* ... */