main.cpp

00001 #include "mbed.h"
00002 #include "stm32f769i_discovery.h"
00003 #include "stm32f769i_discovery_audio.h"
00004  
00005 static void CopyBuffer(int16_t *pbuffer1, int16_t *pbuffer2, uint16_t BufferSize);
00006  
00007 #define SCRATCH_BUFF_SIZE  1024
00008 #define RECORD_BUFFER_SIZE  4096
00009  
00010 typedef enum {
00011     BUFFER_OFFSET_NONE = 0,
00012     BUFFER_OFFSET_HALF = 1,
00013     BUFFER_OFFSET_FULL = 2,
00014 } BUFFER_StateTypeDef;
00015  
00016 volatile uint32_t  audio_rec_buffer_state = BUFFER_OFFSET_NONE;
00017 int32_t Scratch[SCRATCH_BUFF_SIZE];
00018  
00019 /* Buffer containing the PCM samples coming from the microphone */
00020 int16_t RecordBuffer[RECORD_BUFFER_SIZE];
00021  
00022 /* Buffer used to stream the recorded PCM samples towards the audio codec. */
00023 int16_t PlaybackBuffer[RECORD_BUFFER_SIZE];
00024  
00025 int main()
00026 {
00027     uint32_t audio_loop_back_init = RESET ;
00028  
00029     printf("\n\nAUDIO LOOPBACK EXAMPLE FOR DISCO-F769NI START:\n");
00030  
00031     /* Initialize Audio Recorder with 4 channels to be used */
00032     if (BSP_AUDIO_IN_Init(BSP_AUDIO_FREQUENCY_44K, DEFAULT_AUDIO_IN_BIT_RESOLUTION, 2*DEFAULT_AUDIO_IN_CHANNEL_NBR) == AUDIO_ERROR) {
00033         printf("BSP_AUDIO_IN_Init error\n");
00034     }
00035  
00036     /* Allocate scratch buffers */
00037     if (BSP_AUDIO_IN_AllocScratch (Scratch, SCRATCH_BUFF_SIZE) == AUDIO_ERROR) {
00038         printf("BSP_AUDIO_IN_AllocScratch error\n");
00039     }
00040  
00041     /* Start Recording */
00042     if (BSP_AUDIO_IN_Record((uint16_t*)&RecordBuffer[0], RECORD_BUFFER_SIZE) == AUDIO_ERROR) {
00043         printf("BSP_AUDIO_IN_Record error\n");
00044     }
00045     uint8_t ChannelNumber = BSP_AUDIO_IN_GetChannelNumber();
00046  
00047     audio_rec_buffer_state = BUFFER_OFFSET_NONE;
00048  
00049     while (1) {
00050         /* 1st or 2nd half of the record buffer ready for being copied to the playbakc buffer */
00051         if(audio_rec_buffer_state != BUFFER_OFFSET_NONE) {
00052             /* Copy half of the record buffer to the playback buffer */
00053             if(audio_rec_buffer_state == BUFFER_OFFSET_HALF) {
00054                 CopyBuffer(&PlaybackBuffer[0], &RecordBuffer[0], RECORD_BUFFER_SIZE/2);
00055                 if (audio_loop_back_init == RESET) {
00056                     /* Initialize the audio device*/
00057                     if (BSP_AUDIO_OUT_Init(OUTPUT_DEVICE_HEADPHONE, 70, BSP_AUDIO_FREQUENCY_44K) == AUDIO_ERROR) {
00058                         printf("BSP_AUDIO_OUT_Init error\n");
00059                     }
00060                     if(ChannelNumber > 2) {
00061                         BSP_AUDIO_OUT_SetAudioFrameSlot(CODEC_AUDIOFRAME_SLOT_0123);
00062                     } else {
00063                         BSP_AUDIO_OUT_SetAudioFrameSlot(CODEC_AUDIOFRAME_SLOT_02);
00064                     }
00065  
00066                     /* Play the recorded buffer */
00067                     if (BSP_AUDIO_OUT_Play((uint16_t *) &PlaybackBuffer[0], 2*RECORD_BUFFER_SIZE) == AUDIO_ERROR) {
00068                         printf("BSP_AUDIO_OUT_Play error\n");
00069                     }
00070                     /* Audio device is initialized only once */
00071                     audio_loop_back_init = SET;
00072                 }
00073  
00074  
00075             } else { /* if(audio_rec_buffer_state == BUFFER_OFFSET_FULL)*/
00076                 CopyBuffer(&PlaybackBuffer[RECORD_BUFFER_SIZE/2], &RecordBuffer[RECORD_BUFFER_SIZE/2], RECORD_BUFFER_SIZE/2);
00077             }
00078  
00079             /* Wait for next data */
00080             audio_rec_buffer_state = BUFFER_OFFSET_NONE;
00081         }
00082     }
00083 }
00084  
00085 /*-------------------------------------------------------------------------------------
00086        Callbacks implementation:
00087            the callbacks API are defined __weak in the stm32f769i_discovery_audio.c file
00088            and their implementation should be done in the user code if they are needed.
00089            Below some examples of callback implementations.
00090   -------------------------------------------------------------------------------------*/
00091 /**
00092   * @brief Manages the DMA Transfer complete interrupt.
00093   * @param None
00094   * @retval None
00095   */
00096 void BSP_AUDIO_IN_TransferComplete_CallBack(void)
00097 {
00098     audio_rec_buffer_state = BUFFER_OFFSET_FULL;
00099 }
00100  
00101 /**
00102   * @brief  Manages the DMA Half Transfer complete interrupt.
00103   * @param  None
00104   * @retval None
00105   */
00106 void BSP_AUDIO_IN_HalfTransfer_CallBack(void)
00107 {
00108     audio_rec_buffer_state = BUFFER_OFFSET_HALF;
00109 }
00110  
00111 /**
00112   * @brief  Audio IN Error callback function.
00113   * @param  None
00114   * @retval None
00115   */
00116 void BSP_AUDIO_IN_Error_CallBack(void)
00117 {
00118     printf("BSP_AUDIO_IN_Error_CallBack\n");
00119 }
00120  
00121  
00122 /**
00123   * @brief  Copy content of pbuffer2 to pbuffer1
00124   * @param1 BufferOut
00125   * @param2 BufferIn
00126   * @param3 Size
00127   * @retval None
00128   */
00129 static void CopyBuffer(int16_t *pbuffer1, int16_t *pbuffer2, uint16_t BufferSize)
00130 {
00131     uint32_t i = 0;
00132     for(i = 0; i < BufferSize; i++) {
00133         pbuffer1[i] = pbuffer2[i];
00134     }
00135 }