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lib_xua/examples/xua_lite_example/src/audio_hub.xc
2018-11-20 14:07:33 +00:00

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#include "i2s.h"
#include "i2c.h"
#include "xua.h"
#define DEBUG_UNIT XUA_AUDIO_HUB
#define DEBUG_PRINT_ENABLE_XUA_AUDIO_HUB 1
#include "debug_print.h"
#include "mic_array.h"
#include "audio_config.h"
#include "pdm_mic.h"
//Globally declared for 64b alignment
int mic_decimator_fir_data_array[8][THIRD_STAGE_COEFS_PER_STAGE * PDM_MAX_DECIMATION] = {{0}};
mic_array_frame_time_domain mic_audio_frame[2];
[[distributable]]
void AudioHub(server i2s_frame_callback_if i2s,
streaming chanend c_audio,
streaming chanend (&?c_ds_output)[1])
{
int32_t samples_out[NUM_USB_CHAN_OUT] = {0};
int32_t samples_in[NUM_USB_CHAN_IN] = {0};
int32_t clock_nudge = 0;
//PDM mic and decimator
unsigned buffer;
int raw_mics[XUA_NUM_PDM_MICS] = {0};
const unsigned decimatorCount = 1; // Supports up to 4 mics
mic_array_decimator_conf_common_t dcc;
mic_array_decimator_config_t dc[1];
mic_array_frame_time_domain * unsafe current;
mic_array_decimator_set_samprate(DEFAULT_FREQ, mic_decimator_fir_data_array[0], &dcc, dc);
mic_array_decimator_configure(c_ds_output, decimatorCount, dc);
mic_array_init_time_domain_frame(c_ds_output, decimatorCount, buffer, mic_audio_frame, dc);
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 = (MCLK_48/DEFAULT_FREQ)/64;
debug_printf("I2S init\n");
delay_milliseconds(500); //Work around to ensure I2S does not start until enumeration complete so timing does not break for exchange
//This should be ideally done by set config by the host (via xua_buffer) to know we are enumerated
break;
case i2s.receive(size_t n_chans, int32_t in_samps[n_chans]):
for (int i = 0; i < n_chans; i++) samples_in[i] = in_samps[i];
break;
case i2s.send(size_t n_chans, int32_t out_samps[n_chans]):
for (int i = 0; i < n_chans; i++) out_samps[i] = samples_out[i];
break;
//Exchange samples with mics & host
case i2s.restart_check() -> i2s_restart_t restart:
restart = I2S_NO_RESTART; // Keep on looping
timer tmr; int t0, t1; tmr :> t0;
//Transfer samples. Takes about 25 ticks
for (int i = 0; i < NUM_USB_CHAN_OUT; i++) c_audio :> samples_out[i];
if (XUA_ADAPTIVE) c_audio :> clock_nudge;
for (int i = 0; i < NUM_USB_CHAN_IN; i++) c_audio <: raw_mics[i];
//Grab mics. Takes about 200 ticks currently
current = mic_array_get_next_time_domain_frame(c_ds_output, decimatorCount, buffer, mic_audio_frame, dc);
//50 ticks
unsafe {
for (int i = 0; i < XUA_NUM_PDM_MICS; i++) raw_mics[i] = current->data[i][0];
}
//Taking about 160 ticks when adjusting, 100 when not
tmr :> t0;
pll_nudge(clock_nudge);
tmr :> t1;
if (t1-t0 > 500) debug_printf("*%d\n", t1 - t0);
//delay_microseconds(10); //Test backpressure tolerance
break;
}
}
}