Diff: z_example/8_audio.cpp

Revision:

3:35ac9ee7d2d6

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/z_example/8_audio.cpp	Wed Aug 07 05:39:01 2019 +0000
@@ -0,0 +1,148 @@
+// Original
+//      https://os.mbed.com/teams/ST/code/DISCO-F769NI_AUDIO_demo/
+//
+// Modified by K.Arai
+//      July 23rd, 2019
+//
+
+#include "select_program.h"
+//#define EXAMPLE_8_AUDIO
+#ifdef EXAMPLE_8_AUDIO
+
+#include "mbed.h"
+#include "stm32f769i_discovery.h"
+#include "stm32f769i_discovery_audio.h"
+
+Serial pc(USBTX, USBRX, 115200);
+
+static void CopyBuffer(int16_t *pbuffer1, int16_t *pbuffer2, uint16_t BufferSize);
+
+#define SCRATCH_BUFF_SIZE  1024
+#define RECORD_BUFFER_SIZE  4096
+
+typedef enum {
+    BUFFER_OFFSET_NONE = 0,
+    BUFFER_OFFSET_HALF = 1,
+    BUFFER_OFFSET_FULL = 2,
+} BUFFER_StateTypeDef;
+
+volatile uint32_t  audio_rec_buffer_state = BUFFER_OFFSET_NONE;
+int32_t Scratch[SCRATCH_BUFF_SIZE];
+
+/* Buffer containing the PCM samples coming from the microphone */
+int16_t RecordBuffer[RECORD_BUFFER_SIZE];
+
+/* Buffer used to stream the recorded PCM samples towards the audio codec. */
+int16_t PlaybackBuffer[RECORD_BUFFER_SIZE];
+
+int main()
+{
+    uint32_t audio_loop_back_init = RESET ;
+
+    printf("\n\nAUDIO LOOPBACK EXAMPLE FOR DISCO-F769NI START:\n");
+
+    /* Initialize Audio Recorder with 4 channels to be used */
+    if (BSP_AUDIO_IN_Init(BSP_AUDIO_FREQUENCY_44K, DEFAULT_AUDIO_IN_BIT_RESOLUTION, 2*DEFAULT_AUDIO_IN_CHANNEL_NBR) == AUDIO_ERROR) {
+        printf("BSP_AUDIO_IN_Init error\n");
+    }
+
+    /* Allocate scratch buffers */
+    if (BSP_AUDIO_IN_AllocScratch (Scratch, SCRATCH_BUFF_SIZE) == AUDIO_ERROR) {
+        printf("BSP_AUDIO_IN_AllocScratch error\n");
+    }
+
+    /* Start Recording */
+    if (BSP_AUDIO_IN_Record((uint16_t*)&RecordBuffer[0], RECORD_BUFFER_SIZE) == AUDIO_ERROR) {
+        printf("BSP_AUDIO_IN_Record error\n");
+    }
+    uint8_t ChannelNumber = BSP_AUDIO_IN_GetChannelNumber();
+
+    audio_rec_buffer_state = BUFFER_OFFSET_NONE;
+
+    while (1) {
+        /* 1st or 2nd half of the record buffer ready for being copied to the playbakc buffer */
+        if(audio_rec_buffer_state != BUFFER_OFFSET_NONE) {
+            /* Copy half of the record buffer to the playback buffer */
+            if(audio_rec_buffer_state == BUFFER_OFFSET_HALF) {
+                CopyBuffer(&PlaybackBuffer[0], &RecordBuffer[0], RECORD_BUFFER_SIZE/2);
+                if (audio_loop_back_init == RESET) {
+                    /* Initialize the audio device*/
+                    if (BSP_AUDIO_OUT_Init(OUTPUT_DEVICE_HEADPHONE, 70, BSP_AUDIO_FREQUENCY_44K) == AUDIO_ERROR) {
+                        printf("BSP_AUDIO_OUT_Init error\n");
+                    }
+                    if(ChannelNumber > 2) {
+                        BSP_AUDIO_OUT_SetAudioFrameSlot(CODEC_AUDIOFRAME_SLOT_0123);
+                    } else {
+                        BSP_AUDIO_OUT_SetAudioFrameSlot(CODEC_AUDIOFRAME_SLOT_02);
+                    }
+
+                    /* Play the recorded buffer */
+                    if (BSP_AUDIO_OUT_Play((uint16_t *) &PlaybackBuffer[0], 2*RECORD_BUFFER_SIZE) == AUDIO_ERROR) {
+                        printf("BSP_AUDIO_OUT_Play error\n");
+                    }
+                    /* Audio device is initialized only once */
+                    audio_loop_back_init = SET;
+                }
+
+
+            } else { /* if(audio_rec_buffer_state == BUFFER_OFFSET_FULL)*/
+                CopyBuffer(&PlaybackBuffer[RECORD_BUFFER_SIZE/2], &RecordBuffer[RECORD_BUFFER_SIZE/2], RECORD_BUFFER_SIZE/2);
+            }
+
+            /* Wait for next data */
+            audio_rec_buffer_state = BUFFER_OFFSET_NONE;
+        }
+    }
+}
+
+/*-------------------------------------------------------------------------------------
+       Callbacks implementation:
+           the callbacks API are defined __weak in the stm32f769i_discovery_audio.c file
+           and their implementation should be done in the user code if they are needed.
+           Below some examples of callback implementations.
+  -------------------------------------------------------------------------------------*/
+/**
+  * @brief Manages the DMA Transfer complete interrupt.
+  * @param None
+  * @retval None
+  */
+void BSP_AUDIO_IN_TransferComplete_CallBack(void)
+{
+    audio_rec_buffer_state = BUFFER_OFFSET_FULL;
+}
+
+/**
+  * @brief  Manages the DMA Half Transfer complete interrupt.
+  * @param  None
+  * @retval None
+  */
+void BSP_AUDIO_IN_HalfTransfer_CallBack(void)
+{
+    audio_rec_buffer_state = BUFFER_OFFSET_HALF;
+}
+
+/**
+  * @brief  Audio IN Error callback function.
+  * @param  None
+  * @retval None
+  */
+void BSP_AUDIO_IN_Error_CallBack(void)
+{
+    printf("BSP_AUDIO_IN_Error_CallBack\n");
+}
+
+
+/**
+  * @brief  Copy content of pbuffer2 to pbuffer1
+  * @param  None
+  * @retval None
+  */
+static void CopyBuffer(int16_t *pbuffer1, int16_t *pbuffer2, uint16_t BufferSize)
+{
+    uint32_t i = 0;
+    for(i = 0; i < BufferSize; i++) {
+        pbuffer1[i] = pbuffer2[i];
+    }
+}
+
+#endif