heart rate

In this article we look at another interesting idea for an ESP32., its an ESP32 heart rate monitor kit.

Its an all in one development kit which contains the development board, a touch enabled LCD display and its all contained in a typical finger sensor that you get for checking your blood oxygen levels.

Pinout

Features

Chipset: ESP32 WIFI/Bluetooth
USB TO TTL: CP2104
LCD: 0.96 IPS LCD
Heart rate blood oxygen sensor: MAX30102
Six-axis attitude sensor chip: MPU6050
RTC: PCF8563
Customizable buttons: Button
Battery: 200mah
Charging voltage and current: 5V, 500mah

Individual sensors

MAX30102

The MAX30102 is an integrated pulse oximetry and heart-rate monitor biosensor module. It includes internal LEDs, photodetectors, optical elements, and low-noise electronics with ambient light rejection. The MAX30102 provides a complete system solution to ease the design-in process for mobile and wearable devices.

The MAX30102 operates on a single 1.8V power supply and a separate 3.3V power supply for the internal LEDs. Communication is through a standard I²C-compatible interface. The module can be shut down through software with zero standby current, allowing the power rails to remain powered at all times.

MPU-6050

The MPU-6050 devices combine a 3-axis gyroscope and a 3-axis accelerometer on the same silicon die, together with an onboard Digital Motion Processor™ (DMP™), which processes complex 6-axis MotionFusion algorithms.

The device can access external magnetometers or other sensors through an auxiliary master I²C bus, allowing the devices to gather a full set of sensor data without intervention from the system processor.

PCF8563

The PCF8563 is a CMOS1 Real-Time Clock (RTC) and calendar optimized for low power
consumption. A programmable clock output, interrupt output, and voltage-low detector are
also provided.

All addresses and data are transferred serially via a two-line bidirectional I2C-bus.

Maximum bus speed is 400 kbit/s. The register address is incremented automatically after each written or read data byte.

Development

The files are available on the github archive – https://github.com/Xinyuan-LilyGO/LilyGo-HeartRate-Kit

Download all the files from the github repository above

1. Install the correct serial port driver CP210X Driver
2. Change src/main.cpp to src.ino
3. Copy the files in the lib directory to ~/Arduino/libraries, Windows users copy to Documents/Arduino/libraries
4. Double-click to open src/src.ino
5. Change the port to the correct port and select upload

Purchase

The development board costs about £30

LILYGO®TTGO Heart Rate Programming Development Kit ESP32-D0WDQ6-V3 Flash 16MB WIFI Bluetooth IPS 0.96 LCD – Buy here