A simple thermocouple reader project that sends temperature measurements every second over GATT notifications.
For this project I'm using a cheap ESP32-C3 dev board (esp32c3_luatos_core) and a MAX31855 (Thermocouple-to-Digital Converter) module. Any BLE-capable board that is supported by Zephyr should work, you just need to update the dtoverlay accordingly.
Firmware is based on the ESS example from Zephyr, and the client was based on the GATT notification example from Bleak.
On a computer that has BLE support, run python ./client.py --name "THERMOCOUPLE" 00002a6e-0000-1000-8000-00805f9b34fb to start logging temperat readings to a csv file. The Bluetooth device name is defined with CONFIG_BT_DEVICE_NAME in prj.conf and can be changed.