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i2s_driver_config_t i2s_config = {
			.mode = I2S_MODE_MASTER | I2S_MODE_RX,      // Only RX
			.sample_rate = I2S_SAMPLE_RATE, // 96000/48000
			.bits_per_sample = I2S_SAMPLE_BITS, // 32 bits
			.channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,           //2-channels
			.communication_format = I2S_COMM_FORMAT_STAND_I2S,
			.dma_buf_count = I2S_DMA_BUF_CNT, //8 Number of DMA buffer
			.dma_buf_len = I2S_DMA_BUF_LEN, // 128 //Size of each DMA buffer in Sample, 1024 * <Size of each sample which is 8 Bytes > = 8K
			.use_apll = true,
			.fixed_mclk = MASTER_CLK, //(12288000 * 2) 
			.tx_desc_auto_clear = true, //I2S auto clear tx descriptor if there is underflow condition (helps in avoiding noise in case of data unavailability)
			.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1, //Interrupt level 1

Code: Select all

i2s_driver_config_t i2s_config = {
			.mode = I2S_MODE_MASTER | I2S_MODE_RX,      // Only RX
			.sample_rate = I2S_SAMPLE_RATE, // 96000/48000
			.bits_per_sample = I2S_SAMPLE_BITS, // 32 bits
			.channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,           //2-channels
			.communication_format = I2S_COMM_FORMAT_STAND_I2S,
			.dma_buf_count = I2S_DMA_BUF_CNT, //8 Number of DMA buffer
			.dma_buf_len = I2S_DMA_BUF_LEN, // 128 Size of each DMA buffer in Sample, 1024 * <Size of each sample which is 8 Bytes > = 8K
			.use_apll = false,
			.fixed_mclk = 0,//MASTER_CLK, //(12288000 * 2)
			.tx_desc_auto_clear = true, //I2S auto clear tx descriptor if there is underflow condition (helps in avoiding noise in case of data unavailability)
			.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1, //Interrupt level 1
			//.mclk_multiple = I2S_MCLK_MULTIPLE_256,
	};
	i2s_pin_config_t pin_config = {
			.bck_io_num = I2S_BCK_IO,
			.ws_io_num = I2S_WS_IO,
			.data_out_num = I2S_DO_IO,
			.data_in_num = I2S_DI_IO,
			.mck_io_num = I2S_MCK_IO
			};

	i2s_driver_install(I2S_NUM, &i2s_config, 4, &m_i2sQueue);
	i2s_set_pin(I2S_NUM, &pin_config);

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int i2s_read_len = 128*8;
struct AMessage
{
 char ucData[ 128*8 ];
} xMessage;
	struct AMessage *pxMessage;
	m_i2s_rcv_Queue = xQueueCreate(8, sizeof( struct AMessage * ));
while (1) {
		// wait for some data to arrive on the queue
		i2s_event_t evt;

		if (xQueueReceive(m_i2sQueue, &evt, portMAX_DELAY) == pdPASS) {
			if (evt.type == I2S_EVENT_RX_DONE) {
				size_t bytesRead = 0;
				//do {
					// read data from the I2S peripheral
					i2s_read(I2S_NUM, (void*)pxMessage->ucData, i2s_read_len, &bytesRead, 10);
					// process the raw data
					pxMessage = &xMessage;
					if (xQueueSendToBack(m_i2s_rcv_Queue,(void *)&pxMessage,(TickType_t )portMAX_DELAY) != pdPASS ) {
						//printf("Send message failed\n");
					}
					memset(pxMessage->ucData,0,sizeof(struct AMessage));
				//} while (bytesRead > 0);
			} 
		}
	}
	

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#define FLASH_RECORD_SIZE         	((I2S_CHANNEL_NUM * I2S_SAMPLE_RATE * I2S_SAMPLE_BITS / 8 ) // 1 sec

	struct BMessage *pxRxedMessage;
	while (1) {
		if (xQueueReceive(m_i2s_rcv_Queue, &pxRxedMessage,
		portMAX_DELAY) == pdPASS) {
#if 1
			if (flash_wr_size < FLASH_RECORD_SIZE) {
				//read data from I2S bus, in this case, from ADC.
				fseek(f, flash_wr_size, SEEK_SET);
				fwrite(pxRxedMessage->ucData, 1, i2s_read_len, f);
				flash_wr_size += i2s_read_len;
				memset(pxRxedMessage->ucData,0,sizeof(struct BMessage));
			}
			if (flash_wr_size >= FLASH_RECORD_SIZE) {
				ESP_LOGI(TAG, "flash_wr_size %d, FLASH_RECORD_SIZE %d\n",
						flash_wr_size, FLASH_RECORD_SIZE);
				fclose(f);
				fflush(f);
				printf("Done.\n");
				vTaskDelete(NULL);
			}
#endif
		}
	}

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//I2S DMA buffer count
#define I2S_DMA_BUF_CNT				16
//I2S DMA buffer length in samples where, Size of each sample is 8 bytes
#define I2S_DMA_BUF_LEN				128
size_t bytesRead = 0;

while (1) {
				esp_err_t ret = i2s_read(I2S_NUM, (void*)pxMessage->ucData, i2s_read_len, &bytesRead, portMAX_DELAY);
				if (ret != ESP_OK || bytesRead == 0) {
				            printf("i2s read failed. read status %d, read bytes %d\n", ret, bytesRead);
				        } else {
							// process the raw data
								pxMessage = &xMessage;
								if (xQueueSendToBack(m_i2s_rcv_Queue,(void *)&pxMessage,(TickType_t )portMAX_DELAY) != pdPASS ) {
									printf("Send message failed\n");
								}
				        }
	}