[参考译文] TAS2560：音频 I2S

https://e2e.ti.com/support/audio-group/audio/f/audio-forum/1273017/tas2560-audio-i2s

尊敬的先生：

我最终让 TAS2560播放8 kHz 16位声音。 然而,声音不会变成它被认为的方式。 我已附加两个文件

1)它会播放音频文件、说明  "所有过境均有步行标志"  

2) 2)生成的1kHz 正弦波、具有以下功能：

uint32_t generate_stereo_tone(uint16_t *buffer, unsigned int sample_rate, double duration, double frequency, bool reset, uint16_t writeBufferSize)
{
    unsigned int num_samples = (unsigned int)(sample_rate * duration);
    short amplitude = 32767; // 16-bit maximum amplitude
    static unsigned int k = 0;
    uint16_t maxBufferSize=(writeBufferSize/2)-1;
    int addr=0;
    uint16_t test=0;

    if (reset == true || k>=num_samples)
    {
        k =1;
    }
    else{
        for (unsigned int i = k; i < num_samples; i++)
        {
            double time = (double)i / sample_rate;

           buffer[2 * (i-k)+1] = (short)(amplitude * sin(2 * M_PI * frequency * time)); // Left channel
           buffer[2 * (i - k)] = 0;                                           // Right channel (silence)


            if ((i - k) ==maxBufferSize)
            {
                k = i;
                return (num_samples-i);
            }
        }
    }
}

e2e.ti.com/.../1-khz.m4ae2e.ti.com/.../Walk-SIgn-On.m4a

您能不能建议什么必须是问题,有时它感觉我没有给它足够的数据,但似乎很难相信,因为我有4个写入缓冲区,每一个1024字节下面是我的 i2x 设置代码:

void I2S_Setup()
{
    // Initialize the I2S driver
    I2S_init();
    I2S_Params i2sParams;

    // Initialize I2S opening parameters
    //     I2S_Params i2sParams;
    I2S_Params_init(&i2sParams);
    i2sParams.samplingFrequency = SAMPLE_RATE;
    i2sParams.fixedBufferLength = WRITE_BUF_LENGTH * 2;
    i2sParams.bitsPerWord = 16;
    i2sParams.writeCallback = writeCallbackFxn;
    i2sParams.readCallback = readCallbackFxn;
    i2sParams.errorCallback = errCallbackFxn;
    i2sParams.CCLKDivider = 4;
    i2sParams.isDMAUnused = true;

    i2sHandle = I2S_open(CONFIG_I2S_0, &i2sParams);

    I2S_startClocks(i2sHandle);
}

这是我的游戏主题:

void *playAudioThread(void *arg0)
{

    int k;
    I2S_Transaction *lastAchievedTransaction;
    bool static firstTime = true;
    uint32_t offset;

    uint32_t events;
    printf("Transaction1 address = 0x%x  writeBuf1 address = 0x%x\n", &i2sWrite1, &writeBuf1);
    printf("Transaction2 address = 0x%x  writeBuf2 address = 0x%x\n", &i2sWrite2, &writeBuf2);
    printf("Transaction3 address = 0x%x  writeBuf3 address = 0x%x\n", &i2sWrite3, &writeBuf3);
    printf("Transaction4 address = 0x%x  writeBuf4 address = 0x%x\n\n\n", &i2sWrite4, &writeBuf4);


    //initAudioBuffers();
   
    I2S_Setup();

    uint32_t bytesRemaining = 0;

    while (1)
    {

        if (playStop == true)
        {
            if(firstTime == true)
            {
                initAudioBuffers();
                bytesRemaining=preload_Config_AudioBuffers(writeBuf1, writeBuf2, writeBuf3, writeBuf4, playFile, 0, WRITE_BUF_LENGTH);
                firstTime = false;
                I2S_setWriteQueueHead(i2sHandle, &i2sWrite1);
                I2S_startWrite(i2sHandle);
                offset=0;
            }


            if (writeFinished == true)
            {

                if(transactionFinished != NULL)
                {


                    // Need a critical section to be sure to have corresponding bufPtr and bufSize
                     uintptr_t key = HwiP_disable();
                     uint16_t *buf = transactionFinished->bufPtr;
                     uint16_t bufLength = transactionFinished->bufSize / sizeof(uint16_t);
                     bytesRemaining = loadAudioChunk(buf, playFile, offset, WRITE_BUF_LENGTH);
                     offset=offset+WRITE_BUF_LENGTH;
                     HwiP_restore(key);
                     List_put(&i2sWriteList, (List_Elem*)transactionFinished);
                    // audio_console_print_function(console_debug,"Reload Buffer");
                }

//
                if (bytesRemaining <= 0x100)
                {
                   endTicks = Clock_getTicks();
                    elapsedTimeTicks = endTicks - startTicks;
                    Task_sleep(CLOCK_MS(150));
                    I2S_stopWrite(i2sHandle);
                    // I2S_stopClocks(i2sHandle);
                    StopSound();
                    bytesRemaining = 0;
                    firstTime = true;
                    playStop=false;
                    writeFinished = false;
                    audio_console_print_function(console_debug,"Sound file Played");
                }
                writeFinished = false;
                //audio_console_print_function(console_debug,"transaction complete %x ,bytes remaining %d, no of completions: %d",transactionFinished, bytesRemaining,transactionFinished->numberOfCompletions);
            }
            else
            {
                 Task_sleep(CLOCK_MS(5));
            }
        }
        else
        {
            Task_sleep(CLOCK_MS(100));
            I2S_stopWrite(i2sHandle);
        }
    }
}

写入回调

static void writeCallbackFxn(I2S_Handle handle, int_fast16_t status, I2S_Transaction *transactionPtr) {

     // We must remove the previous transaction (the current one is not over)
       transactionFinished = (I2S_Transaction*)List_prev(&transactionPtr->queueElement);
//      audio_console_print_function(console_debug,"transaction complete prev%x",(I2S_Transaction*)List_prev(&transactionPtr->queueElement));
//      audio_console_print_function(console_debug,"transaction complete next%x",(I2S_Transaction*)List_next(&transactionPtr->queueElement));
    // audio_console_print_function(console_debug,"transaction complete %x",transactionFinished);
      if(transactionFinished != NULL){
          // Remove the finished transaction from the write queue
          List_remove(&i2sWriteList, (List_Elem*)transactionFinished);

          writeFinished=true;
      }
      if(status>I2S_TRANSACTION_SUCCESS)
      {
          audio_console_print_function(console_debug,"I2S Error %x", status);
      }
      if(status==I2S_ALL_TRANSACTIONS_SUCCESS)
      {
          audio_console_print_function(console_debug,"Buffer UnderRun");
          writeFinished=false;
      }


 }