Mic

Mic is used to control the built-in microphone inside the host device. Below is the detailed Mic support for the host:

Controller	SPM1423	ES7210
AtomS3
AtomS3 Lite
AtomS3U	✔
StampS3
CoreS3		✔
Core2	✔
TOUGH

Micropython Example:

# SPDX-FileCopyrightText: 2024 M5Stack Technology CO LTD
#
# SPDX-License-Identifier: MIT

import os, sys, io
import M5
from M5 import *
import time


label0 = None


rec_data = None


def setup():
    global label0, rec_data

    M5.begin()
    Widgets.fillScreen(0x222222)
    label0 = Widgets.Label("label0", 123, 58, 1.0, 0xFFFFFF, 0x222222, Widgets.FONTS.DejaVu18)

    Speaker.begin()
    Speaker.setVolumePercentage(1)
    Speaker.end()
    Mic.begin()
    rec_data = bytearray(8000 * 5)
    label0.setText(str("rec..."))
    Mic.record(rec_data, 8000, False)
    while Mic.isRecording():
        time.sleep_ms(500)
    Mic.end()
    Speaker.begin()
    label0.setText(str("play..."))
    Speaker.playRaw(rec_data, 8000)
    while Speaker.isPlaying():
        time.sleep_ms(500)
    label0.setText(str("done"))


def loop():
    global label0, rec_data
    M5.update()


if __name__ == "__main__":
    try:
        setup()
        while True:
            loop()
    except (Exception, KeyboardInterrupt) as e:
        try:
            from utility import print_error_msg

            print_error_msg(e)
        except ImportError:
            print("please update to latest firmware")

UIFLOW2 Example:

cores3_mic_example.m5f2

class Mic

Important

Methods of the Mic Class heavily rely on M5.begin() and M5.update() .

All calls to methods of Mic objects should be placed after M5.begin() , and M5.update() should be called in the main loop.

Methods

Mic.config([cfg:mic_config_t])

Mic.config('param')

Mic.config(param=value)

Get or set the parameters of the Mic object.

When no parameters are passed, it returns an object of mic_config_t. When a mic_config_t object is passed, Mic sets all supported parameters of the Mic.

When passing parameters from the table below, Mic will get or set the passed parameters.

The following parameters are supported:

Parameter	Type	Description
pin_data_in	(integer)	Serial data line of I2S, representing audio data in binary complement.
pin_bck	(integer)	Serial clock line of I2S, corresponding to each bit of digital audio data.
pin_mck	(integer)	Master clock line of I2S. Generally, to better synchronize between systems, increase the MCLK signal, MCLK frequency = 256 * sampling frequency.
pin_ws	(integer)	Frame clock of I2S, used to switch left and right channel data.
sample_rate	(integer)	Target sampling rate of input audio.
stereo	(boolean)	Use stereo output.
over_sampling	(integer)	Number of times to average the sampling.
magnification	(integer)	Multiplier of the input value.
noise_filter_level	(integer)	Coefficient of the previous value used for noise filtering.
use_adc	(boolean)	Use analog input microphone (only pin_data_in is needed).
dma_buf_len	(integer)	DMA buffer length of I2S.
dma_buf_count	(integer)	Number of DMA buffers of I2S.
task_priority	(integer)	Priority of background tasks.
task_pinned_core	(integer)	CPU used by background tasks.
i2s_port	(integer)	I2S port.

UIFLOW2:

Read property:

Python:

Mic.config("pin_data_in")

Set property:

Python:

Mic.config(pin_data_in=1)

Mic.begin() → bool

Start the Mic function. Returns True if successful.

UIFLOW2:

Mic.end() → bool

Stop the Mic function. Returns True if successful.

UIFLOW2:

Mic.isRunning() → bool

Check if Mic is running. Returns a boolean value.

UIFLOW2:

Mic.isEnabled() → bool

Check if Mic is enabled. Returns a boolean value.

UIFLOW2:

Mic.isRecording() → int

Check if Mic is recording. Returns an integer value.

Return values:

• 0=not recording

• 1=recording (There’s room in the queue)

• 2=recording (There’s no room in the queue.)

UIFLOW2:

Mic.setSampleRate(sample_rate) → None

Set the sampling rate. The parameter sample_rate generally includes 8000, 11025, 22050, 32000, 44100.

UIFLOW2:

Mic.record(rec_data[, rate[, stereo]]) → bool

Record audio data.

The parameter rec_data requires passing a buffer. The parameter rate generally includes 8000, 11025, 22050, 32000, 44100, with a default of 8000. The parameter stereo is passed as True or False.

UIFLOW2:

class mic_config_t

mic_config_t.pin_data_in: int

Serial data line of I2S, representing audio data in binary complement.

mic_config_t.pin_bck: int

Serial clock line of I2S, corresponding to each bit of digital audio data.

mic_config_t.pin_mck: int

Master clock line of I2S. Generally, to better synchronize between systems, increase the MCLK signal, MCLK frequency = 256 * sampling frequency.

mic_config_t.pin_ws: int

Frame clock of I2S, used to switch left and right channel data.

mic_config_t.sample_rate: int

Target sampling rate of input audio.

mic_config_t.stereo: bool

Use stereo output.

mic_config_t.over_sampling: int

Number of times to average the sampling.

mic_config_t.magnification: int

Multiplier of the input value.

mic_config_t.noise_filter_level: int

Coefficient of the previous value used for noise filtering.

mic_config_t.use_adc: bool

Use analog input microphone (only pin_data_in is needed).

mic_config_t.dma_buf_len: int

DMA buffer length of I2S.

mic_config_t.dma_buf_count: int

Number of DMA buffers of I2S.

mic_config_t.task_priority: int

Priority of background tasks.

mic_config_t.task_pinned_core: int

CPU used by background tasks.

mic_config_t.i2s_port: int

I2S port.