File content as of revision 6:e689075b04ed:

#include "mbed.h"
#include "stm32746g_discovery_audio.h"
#include "stm32746g_discovery_sdram.h"
#include "stm32746g_discovery_lcd.h"

typedef enum {
    BUFFER_OFFSET_NONE = 0,
    BUFFER_OFFSET_HALF = 1,
    BUFFER_OFFSET_FULL = 2,
} BUFFER_StateTypeDef;


// #define AUDIO_BLOCK_SIZE   ((uint32_t)512)
#define AUDIO_BLOCK_SIZE   ((uint32_t)256)

#define SDRAM_DEVICE_ADDR_AUDIO_MEM  ((uint32_t)0xC00A0000)
#define AUDIO_BUFFER_IN     SDRAM_DEVICE_ADDR_AUDIO_MEM
#define AUDIO_BUFFER_OUT   (AUDIO_BUFFER_IN + (AUDIO_BLOCK_SIZE * 2))

#define OSC_START_X_POS     10
#define OSC_LINE_SIZE       256
#define L_CHANNEL_Y_POS     120
#define R_CHANNEL_Y_POS     220

volatile uint32_t  audio_rec_buffer_state = BUFFER_OFFSET_NONE;
static void Draw_Trace(uint16_t Xpos, uint16_t Ypos, uint32_t Mem_start, uint16_t Length);

int main()
{
    
    BSP_LCD_Init();
    BSP_LCD_LayerDefaultInit(LTDC_ACTIVE_LAYER, LCD_FB_START_ADDRESS);
    BSP_LCD_SelectLayer(LTDC_ACTIVE_LAYER);

    BSP_LCD_Clear(LCD_COLOR_BLACK);
    BSP_LCD_SetFont(&LCD_DEFAULT_FONT);
        

    BSP_LCD_SetBackColor(LCD_COLOR_BLACK);
    BSP_LCD_SetTextColor(LCD_COLOR_ORANGE);
    BSP_LCD_DisplayStringAt(0, 0, (uint8_t *)"487 Audio Loopback Test Code", LEFT_MODE);

    printf("\n\nAUDIO LOOPBACK EXAMPLE START:\n");

    BSP_AUDIO_IN_OUT_Init(INPUT_DEVICE_DIGITAL_MICROPHONE_2, OUTPUT_DEVICE_HEADPHONE, DEFAULT_AUDIO_IN_FREQ, DEFAULT_AUDIO_IN_BIT_RESOLUTION, DEFAULT_AUDIO_IN_CHANNEL_NBR);
    printf("AUDIO loop from digital micro (U20 & U21 components on board) to headphone (CN10 jack connector)\n");

    BSP_LCD_DisplayStringAt(10, 20, (uint8_t *)"SDRAM Initialization", LEFT_MODE);


    /* Initialize SDRAM buffers */
    BSP_SDRAM_Init();
    memset((uint16_t *)AUDIO_BUFFER_IN, 0, AUDIO_BLOCK_SIZE * 2);
    memset((uint16_t *)AUDIO_BUFFER_OUT, 0, AUDIO_BLOCK_SIZE * 2);
    printf("SDRAM init done\n");

    audio_rec_buffer_state = BUFFER_OFFSET_NONE;

    /* Start Recording */
    if (BSP_AUDIO_IN_Record((uint16_t *)AUDIO_BUFFER_IN, AUDIO_BLOCK_SIZE) != AUDIO_OK) {
        printf("BSP_AUDIO_IN_Record error\n");
    }

    /* Start Playback */
    BSP_AUDIO_OUT_SetAudioFrameSlot(CODEC_AUDIOFRAME_SLOT_02);
    if (BSP_AUDIO_OUT_Play((uint16_t *)AUDIO_BUFFER_OUT, AUDIO_BLOCK_SIZE * 2) != AUDIO_OK) {
        printf("BSP_AUDIO_OUT_Play error\n");
    }


    BSP_LCD_SetTextColor(LCD_COLOR_BLUE);
    uint32_t counter;
    counter = 0;

    char buf[10];

    while (1) {
    /* First Half */

        /* Wait end of half block recording */
        while (audio_rec_buffer_state == BUFFER_OFFSET_HALF) {
        }
        audio_rec_buffer_state = BUFFER_OFFSET_NONE;

        /* Copy recorded 1st half block */
        memcpy((uint16_t *)(AUDIO_BUFFER_OUT), (uint16_t *)(AUDIO_BUFFER_IN), AUDIO_BLOCK_SIZE);

    /* Second Half */

        /* Wait end of one block recording */
        while (audio_rec_buffer_state == BUFFER_OFFSET_FULL) {
        }
        audio_rec_buffer_state = BUFFER_OFFSET_NONE;

        /* Copy recorded 2nd half block */
        memcpy((uint16_t *)(AUDIO_BUFFER_OUT + (AUDIO_BLOCK_SIZE)), (uint16_t *)(AUDIO_BUFFER_IN + (AUDIO_BLOCK_SIZE)), AUDIO_BLOCK_SIZE);

        BSP_LCD_SetTextColor(LCD_COLOR_BLUE);
        BSP_LCD_DrawHLine(OSC_START_X_POS, L_CHANNEL_Y_POS, OSC_LINE_SIZE);
        BSP_LCD_DrawHLine(OSC_START_X_POS, R_CHANNEL_Y_POS, OSC_LINE_SIZE);

        Draw_Trace(OSC_START_X_POS, L_CHANNEL_Y_POS, AUDIO_BUFFER_OUT, 256);
        
        counter++;
        sprintf(buf, "%d", counter);
        BSP_LCD_SetTextColor(LCD_COLOR_RED);
        BSP_LCD_DisplayStringAt(0, 40, (uint8_t *) buf, LEFT_MODE);
    }
}


/**
  * @brief  Draws a trace of the data line.
  * @param  Xpos: X position
  * @param  Ypos: Y position
  * @param  Mem_start: Start of memory location
  * @param  Length: length of trace
  * @retval None
  */
void Draw_Trace(uint16_t Xpos, uint16_t Ypos, uint32_t Mem_start, uint16_t Length)
{
    uint32_t i;
    int data_value;
    char buf[12];
    
    sprintf(buf, "%12d", *((uint32_t*) Mem_start));
    BSP_LCD_DisplayStringAt(0, 60, (uint8_t *) buf, LEFT_MODE);
    
    sprintf(buf, "%12d", *((uint32_t*) Mem_start+1));
    BSP_LCD_DisplayStringAt(0, 80, (uint8_t *) buf, LEFT_MODE);
    
    sprintf(buf, "%12d", *((uint32_t*) Mem_start+2));
    BSP_LCD_DisplayStringAt(0, 100, (uint8_t *) buf, LEFT_MODE);    
    /*
    
    for (i=1; i<=Length; i++)
   {
       data_value = *((uint32_t*) (Mem_start + i));
       BSP_LCD_DrawPixel(Xpos + i, int16_t((int) Ypos + data_value), LCD_COLOR_WHITE);
   }
   */
   
}
    
/* Read data value from SDRAM memory */
//    ret = *(__IO uint32_t*) (hLtdcHandler.LayerCfg[ActiveLayer].FBStartAdress + (4*(Ypos*BSP_LCD_GetXSize() + Xpos)));


/*-------------------------------------------------------------------------------------
       Callbacks implementation:
           the callbacks API are defined __weak in the stm32746g_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");
}