This is the arduino code to create the BLE server to capture the ECG signal and comunicate with the app AWECG.
The sample rate is 250Hz and the resolution is 12 bits. The signal is amplified by an AD8232 and the microcontroller is an ESP32.
- Download the code and open it with the PlatformIO IDE.
- Connect the ESP32 to the computer.
- Upload the code to the ESP32.
- Open the app AWECG and connect to the ESP32.
- Enjoy!
The AD8232 get the ECG signal to get I derivation. It's necessary to connect the AD8232 to the ESP32 with the following pins:
| AD8232 | ESP32 |
|---|---|
| GND | GND |
| 3.3v | 3.3V |
| OUTPUT | IO 32 |
| LO+ | NC |
| LO- | NC |
| SDN | IO 14 |
The wake-up button is used to wake-up the ESP32 from deep sleep mode. The Button is connected to the ESP32 using a pull-down resistor. The ESP32 is waked-up when the button is pressed. The button is connected to the ESP32 with the IO 12.