XCore Exchange

Code: Select all

  int32_t samples[8] = {0, 0, 0, 0, 0, 0, 0, 0};

  while (1) {
    select {
    case i2s.init(i2s_config_t &?i2s_config, tdm_config_t &?tdm_config):
      i2s_config.mode = I2S_MODE_I2S;
      i2s_config.mclk_bclk_ratio = (MASTER_CLOCK_FREQUENCY/SAMPLE_FREQUENCY)/64;

      // Set CODECs in reset
      dac_reset.output(0);
      adc_reset.output(0);

      // Select 48Khz family clock (24.576Mhz)
      mclk_select.output(1);
      pll_select.output(0);

      // Allow the clock to settle
      delay_milliseconds(2);

      // Take CODECs out of reset
      dac_reset.output(1);
      adc_reset.output(1);

      reset_codecs(i2c);
      break;

    case i2s.receive(size_t num_chan_in, int32_t sample[num_chan_in]):
      for (size_t i=0; i<num_chan_in; i++) {
          samples[i] = sample[i];
      }
      break;

    case i2s.send(size_t num_chan_out, int32_t sample[num_chan_out]):
      for (size_t i=0; i<num_chan_out; i++){
        sample[i] = samples[i];
      }
      break;


    case i2s.restart_check() -> i2s_restart_t restart:
      restart = I2S_NO_RESTART;
      break;
    }
  }
}

Code: Select all

  int32_t us_data[24] = {0};
unsafe {
[[distributable]]
void i2s_handler(server i2s_callback_if i2s,
                 client i2c_master_if i2c,
                 client interface bufget_i filler
                 ) {
  multichannel_audio_block_s * unsafe buffer = 0; // invalid
  unsigned sample_idx=0;

  p_rst_shared <: 0xF;


  mabs_init_pll(i2c, ETH_MIC_ARRAY);
  i2c_regop_res_t res;
  int i = 0x4A;
  uint8_t data = i2c.read_reg(i, 1, res);

  data = i2c.read_reg(i, 0x02, res);
  data |= 1;
  res = i2c.write_reg(i, 0x02, data); // Power down

  // Setting MCLKDIV2 high if using 24.576MHz.
  data = i2c.read_reg(i, 0x03, res);
  data |= 1;
  res = i2c.write_reg(i, 0x03, data);

  data = 0b01110000;
  res = i2c.write_reg(i, 0x10, data);

  data = i2c.read_reg(i, 0x02, res);
  data &= ~1;
  res = i2c.write_reg(i, 0x02, data); // Power up
  unsigned phase_index = 0;
  while (1) {
    select {
    case i2s.init(i2s_config_t &?i2s_config, tdm_config_t &?tdm_config):
      i2s_config.mode = I2S_MODE_LEFT_JUSTIFIED;
      i2s_config.mclk_bclk_ratio = (MASTER_CLOCK_FREQUENCY/OUTPUT_SAMPLE_RATE)/64;
      break;

    case i2s.restart_check() -> i2s_restart_t restart:
      restart = I2S_NO_RESTART;
      break;

    case i2s.receive(size_t index, int32_t sample):
      break;

    case i2s.send(size_t index) -> int32_t sample:
      if(buffer) {

          if(phase_index == 0){
              int32_t s = buffer->data[index][sample_idx];
              sample = src_us3_voice_input_sample(us_data, src_ff3v_fir_coefs[0], s);
          } else {
              sample = src_us3_voice_get_next_sample(us_data, src_ff3v_fir_coefs[phase_index]);
          }

      } else { // buffer invalid
         sample = 0;
      }
      //xscope_int(index, sample);
      if((index == 1)) {
          phase_index++;
          if(phase_index == 3){
              sample_idx++;
              phase_index = 0;
          }
      }
      if(sample_idx>=FFT_N/2) {
        // end of buffer reached.
        sample_idx = 0;
        filler.get_next_buf(buffer);
        //printf("I2S got next buffer at 0x%x\n", buffer);
      }
      break;
    }
  }
}
}