52 lines
1.5 KiB
C++
52 lines
1.5 KiB
C++
#include <driver/i2s.h>
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#define I2S_WS 6 // LRCL (Word Select)
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#define I2S_SCK 7 // BCLK (Serial Clock)
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#define I2S_SD 8 // DOUT (Serial Data from mic)
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#define I2S_PORT I2S_NUM_0
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#define BUFFER_SIZE 2048 // Larger buffer = fewer calls
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void setup() {
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Serial.begin(1000000); // High-speed serial for streaming audio
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// I2S configuration
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const i2s_config_t i2s_config = {
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.mode = i2s_mode_t(I2S_MODE_MASTER | I2S_MODE_RX),
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.sample_rate = 8000,
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.bits_per_sample = I2S_BITS_PER_SAMPLE_32BIT,
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.channel_format = I2S_CHANNEL_FMT_ONLY_LEFT,
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.communication_format = I2S_COMM_FORMAT_I2S,
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.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1,
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.dma_buf_count = 4,
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.dma_buf_len = BUFFER_SIZE / 4,
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.use_apll = false,
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.tx_desc_auto_clear = false,
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.fixed_mclk = 0
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};
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const i2s_pin_config_t pin_config = {
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.bck_io_num = I2S_SCK,
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.ws_io_num = I2S_WS,
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.data_out_num = I2S_PIN_NO_CHANGE,
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.data_in_num = I2S_SD
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};
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i2s_driver_install(I2S_PORT, &i2s_config, 0, NULL);
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i2s_set_pin(I2S_PORT, &pin_config);
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}
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void loop() {
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uint8_t buffer[BUFFER_SIZE];
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size_t bytes_read;
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if (i2s_read(I2S_PORT, &buffer, BUFFER_SIZE, &bytes_read, portMAX_DELAY) == ESP_OK && bytes_read > 0) {
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for (int i = 0; i < bytes_read; i += 4) {
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int32_t sample_32 = *(int32_t*)&buffer[i];
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int16_t sample_16 = sample_32 >> 12; // Less aggressive shift
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Serial.write((uint8_t*)&sample_16, 2);
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}
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}
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}
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