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한국어 (Korean)
Мови (Ukrainian)

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ESP32-AUDIO-KIT ​

chip:esp32, chip:esp32a1s

The Ai-Thinker ESP32 Audio Kit is a development board for the ESP32 SoC from Espressif, based on Ai-Thinker ESP32-A1S audio module.

Ai-Thinker ESP32 Audio Kit board ​

Features ​

  • ESP32-A1S module
  • Audio Earphones Output
  • Audio LINEIN Input
  • 2 Microphones in the board (stereo audio input)
  • 8 Buttons in the boards (1 RST Button and 7 user buttons)
  • MicroSD card slot

Some of the ESP32 I/O pins are broken out to the board's pin header.

Serial Console ​

UART0 is, by default, the serial console. It connects to the on-board Silabs CP2102 converter and is available on the USB connector (UART label).

It will show up as /dev/ttyUSB[n] where [n] normally is 0 if you don't have another USB/Serial adapter connected in your computer.

Buttons and LEDs ​

Board Buttons ​

There are eight buttons labeled as RST, BOOT, KEY1..KEY6. The RST button is not available to software.

The BOOT button is connected to IO0. On reset it is used as a strapping pin to determine whether the chip boots normally or into the serial bootloader. After reset, however, the BOOT button can be used for software input.

Board LEDs ​

There are several on-board LEDs for that indicate the presence of power and USB activity.

I/O Mapping ​

I/O Signal Notes

0 2 4 5 12 BOOT Button DATA0 SDCard DATA1 SDCard KEY6 Button DATA2 SDCard
13 14 KEY2 Button/DATA3 SDCard CLK SDCard (DIP Switch) 15 18 19 21 22 23 34 36 CMD SDCard/JTAG MTDO KEY5 Button KEY3 Button/LED5 CTRL Audio AMP LED4 KEY4 Button SDCard Detect KEY1 Button (DIP Switch)

Configurations ​

All of the configurations presented below can be tested by running the following commands:

 ./tools/configure.sh esp32-audio-kit:<config_name>
 make flash ESPTOOL_PORT=/dev/ttyUSB0 -j

Where <config_name> is the name of board configuration you want to use, i.e.: nsh, buttons, wifi... Then use a serial console terminal like minicom or picocom configured to 115200 8N1.

audio ​

This configuration uses the I2S0 peripheral and the ES8388 audio codec present on the ESP32-Audio-Kit board to play an audio file streamed over HTTP while connected to a Wi-Fi network.

Simple HTTP server

Prepare a PCM-encoded ([.wav]{.title-ref}) audio file with 16 bits/sample (sampled at 44.1kHz). This file must be placed into a folder in a computer that could be accessed on the same Wi-Fi network the ESP32 will be connecting to.

Python provides a simple HTTP server. [cd]{.title-ref} to the audio file folder on the PC and run:

 python3 -m http.server

Serving HTTP on 0.0.0.0 port 8000 (http://0.0.0.0:8000/)

Look for your PC IP address and test playing the prepared audio on your browser:

After successfully built and flashed, connect the board to the Wi-Fi network:

 nsh> wapi psk wlan0 mypasswd 3
 nsh> wapi essid wlan0 myssid 1
 nsh> renew wlan0

Once connected, open NuttX's player and play the file according to its file name and the IP address of the HTTP server (For example [tone.wav]{.title-ref} and [192.168.1.239:8000]{.title-ref}, respectively):

 nsh> nxplayer
 nxplayer> play http://192.168.1.239:8000/tone.wav

Note

The codec implementation on the LyraT board was validated using 16-bit, 44.1kHz WAV files. Other configurations might not work as expected.

nsh ​

Basic NuttShell configuration (console enabled in UART0, exposed via USB connection by means of FT2232HL converter, at 115200 bps).

wifi ​

Enables Wi-Fi support. You can define your credentials this way:

 make menuconfig
-> Application Configuration
    -> Network Utilities
        -> Network initialization (NETUTILS_NETINIT [=y])
            -> WAPI Configuration

Or if you don't want to keep it saved in the firmware you can do it at runtime:

nsh> wapi psk wlan0 mypasswd 3
nsh> wapi essid wlan0 myssid 1
nsh> renew wlan0

Tip

Please refer to ESP32 Wi-Fi Station Mode <esp32_wi-fi_sta>{.interpreted-text role="ref"} for more information.