@jmiskovic Here is a simplified example, extracted from a private project with some irrelevant parts removed:

import gc
import espidf as esp
from espidf import I2S_MODE
from espidf import I2S_COMM_FORMAT
from espidf import I2S_CHANNEL_FMT
from espidf import I2S_BITS_PER_SAMPLE
from espidf import I2S_CHANNEL
from espidf import GPIO_MODE

class Recorder:
    I2S_PIN_NO_CHANGE = const(-1)
    BYTES_PER_SAMPLE = const(4)
    BYTES_PER_OUTPUT_SAMPLE = const(2)
    OVERSAMPLE_MULTIPLIER = const(1)

    def __init__(self, bclk = 2, dout = 36, ws = 22, freq = 16000, i2s_num = esp.I2S_NUM._0):
        self.bclk = bclk
        self.dout = dout
        self.ws = ws
        self.freq = freq
        self.sample_rate = freq * OVERSAMPLE_MULTIPLIER
        self.i2s_num = i2s_num
        self.bits_per_sample = self.BYTES_PER_SAMPLE * 8
        self.dma_buf_count = 6
        self.dma_buf_len = 1024
        self.bytes_to_read = (self.dma_buf_count * self.dma_buf_len)

        # Init I2S

        self.i2s_config = esp.i2s_config_t({
            'mode': I2S_MODE.MASTER | I2S_MODE.RX,
            'sample_rate': self.sample_rate,
            'bits_per_sample': self.bits_per_sample,
            'communication_format': I2S_COMM_FORMAT.I2S | I2S_COMM_FORMAT.I2S_MSB,
            'channel_format': I2S_CHANNEL_FMT.ONLY_RIGHT,
            'intr_alloc_flags': (1<<1), # ESP_INTR_FLAG_LEVEL1
            'dma_buf_count': self.dma_buf_count,
            'dma_buf_len': self.dma_buf_len,
            'use_apll':0
        })

        self.i2s_pin_config = esp.i2s_pin_config_t({
            'bck_io_num': self.bclk,
            'ws_io_num': self.ws,
            'data_out_num': self.I2S_PIN_NO_CHANGE,
            'data_in_num': self.dout,    
        })

        esp.i2s_driver_install(self.i2s_num, self.i2s_config, 0, None)
        esp.i2s_set_pin(self.i2s_num, self.i2s_pin_config)
        esp.SPH0645_WORKAROUND(self.i2s_num)
        esp.i2s_stop(self.i2s_num)

    def close(self):
        esp.i2s_driver_uninstall(self.i2s_num)

    def record(self):
        input_buf = bytearray(self.bytes_to_read)
        self.input_view = memoryview(input_buf)
        bytes_read_ptr = esp.C_Pointer()
        gc.disable()
        esp.i2s_start(self.i2s_num)

        while self.recording:
            res = esp.i2s_read(self.i2s_num, self.input_view, self.bytes_to_read, bytes_read_ptr, 0)
            if res != 0: raise RuntimeError('i2s_read completed with error %d' % res)
            bytes_read = bytes_read_ptr.uint_val
            if bytes_read == 0: continue
            
            # Do something with input_buf

        esp.i2s_stop(self.i2s_num)
        gc.endale()

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