Home buzzer by BLE Central

call families in their rooms from the home hub computer (BLE devices).

graph LR;
  subgraph Ad[RasPi or etc.]
    A[fa:fa-network-wired BLE devices];
  end
  subgraph Bd[M5 Stack or etc.]
    B((fa:fa-computer-speaker ESP32 device));
  end

  A -- "BLE Adv." --> B;
  B -- "sound" --> C{people};
  D[(wave files)] -- "TF card" --> B;

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Environments

term	descriptions
Hardware	M5 Stack as the Buzzers
Tool	USB Type-C cable
SDK	esp-idf v5.0
Host-OS	Armbian 20.10 (Debian 10)
branch	blecent
.	.
Hardware	RaspberryPi 3B as the home hub computer
SDK	Python Bluez
Host-OS	Raspibian (Debian 9)
branch	blecent-broker
Sounds	wave files

Setup

• hardware: M5 Stack as Home Buzzer.
• hardware: use SBC or Linux machines has BLE devices like RaspberryPi 3B.

Setup your BLE device

graph LR;
  subgraph Ad[RasPi or etc.]
    A[(fa:fa-network-wired BLE devices)];
  end

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install packages for gobject and dbus.

$ apt install python3-gi python3-dbus

• download this repo.

$ git clone https://github.com/kuri65536/homebuzzer.git -b blecent-broker broker
$ cd broker
... optional: edit dbus policy ...
$ python3 buzzerbroker.py --type 2

• now your device advertise alerting and select the 2 wave file.

Setup ESP32 device

graph LR;
  subgraph Bd[M5 Stack or etc.]
    B((fa:fa-computer-speaker ESP32 device));
  end

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(on the host machine)

• install esp-idf, see instruction of esp-idf:

  https://docs.espressif.com/projects/esp-idf/en/latest/esp32/get-started/linux-macos-setup.html

• my point is that specify version number at downloading.

(after toolchains and python setup.)
$ git clone --recursive https://github.com/espressif/esp-idf.git -b v5.0
(then go to setup esp-idf.)

• after setup, download this repo and build.

$ git clone https://github.com/kuri65536/homebuzzer.git
$ cd homebuzzer
$ . /path/to/esp-idf/export.sh
$ idf.py build

• connect M5 Stack to the host machine via USB.

$ idf.py -p /dev/ttyUSB0 flash

• store wave files (as you like it) to TF card,
  and rename them to prefix single numbers:

  • 0ring.wav
  • 1bell.wav
  • 2voice.wav
  • ...

• insert TF card and reset your M5 Stack.
  setup is completed!

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Related documents

TF-Card interface

• M5-Stack pin info:
  https://github.com/kunsen-an/m5stack_espidf_sd_card_write_test

BLE Advertisement

• Advertisement data:
  https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/doc/advertising-api.txt

DAC peripheral

• https://docs.espressif.com/projects/esp-idf/en/v5.0/esp32/api-reference/peripherals/dac.html

Wave file

• http://truelogic.org/wordpress/2015/09/04/parsing-a-wav-file-in-c/
• https://isip.piconepress.com/projects/speech/software/tutorials/production/fundamentals/v1.0/section_02/s02_01_p05.html

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License

this projects is licensed under MIT License.

ESP-IDF is licensed under MIT license, see LICENSE.txt