Project 1 of 8 Basics

I2C address and bus inventory

Run the firmware scan command with each module added separately, then together. Confirm the OLED responds at 0x3C or 0x3D and the MAX30102 at 0x57. Record any address or startup failure before attempting signal experiments.

One of 8 projects in the ESP32 ECG & Optical Pulse Learning Kit — the parts below are from that kit.

// How it works

What you build in this project

I2C address and bus inventory is one focused build from the ESP32 ECG & Optical Pulse Learning Kit. It uses the parts listed below to make a working electronics example, then you can combine it with the other projects in the kit.

Run the firmware scan command with each module added separately, then together. Confirm the OLED responds at 0x3C or 0x3D and the MAX30102 at 0x57. Record any address or startup failure before attempting signal experiments.

Parts used

ESP32U, DIY-003 OLED, MAX30102, breadboard, jumper wires

What to check

Wire the parts, upload the sketch from the kit page, then test this project by watching the Serial Monitor or the output behavior.

What you learn

You learn how the controller reads real sensor signals, makes a decision in code, and turns that result into a useful output.

// Items used

What this project uses

Every item is in the kit — nothing extra to buy.

ESP32U ESP32U Development Board, WiFi Bluetooth IoT NodeMCU-32 Module, DevKitC with TYPE-C Interface, Development Ki… ESP32U

In the kit

DIY-003 OLED 0.96" OLED Display Module 128x64 I2C (White) DIY-003

In the kit

MAX30102 MAX30102 Heart Rate & SpO2 Pulse Oximeter Sensor Module with I2C Interface, INT Pin, 3.3V Logic, Arduino STM3… MAX30102

In the kit

breadboard 830 Tie Point Solderless Breadboard - Full Size Prototyping Circuit Board with Dual Power Rails, for Arduino… DIY-217

In the kit

jumper wires Jumper Wire Assorted Pack 120 Pieces - Male-to-Male, Male-to-Female, Female-to-Female 10cm Ribbon Cables for… DIY-212

In the kit

Build this with

ESP32 ECG & Optical Pulse Learning Kit

All 6 parts in one box, with this project and 7 more to build from them.

AED 101.50 See the kit

Need only these parts? Order them loose · from AED 100.69

Used in this project tick what you still need

ESP32U ESP32U Development Board, WiFi Bluetooth IoT NodeMCU-32 Module, DevKitC with TYPE-C Interface, Development Ki… ESP32U · ×1

AED 33.29

In stock

DIY-003 OLED 0.96" OLED Display Module 128x64 I2C (White) DIY-003 · ×1

AED 19.93

In stock

MAX30102 MAX30102 Heart Rate & SpO2 Pulse Oximeter Sensor Module with I2C Interface, INT Pin, 3.3V Logic, Arduino STM3… MAX30102 · ×1

AED 22.45

In stock

breadboard 830 Tie Point Solderless Breadboard - Full Size Prototyping Circuit Board with Dual Power Rails, for Arduino… DIY-217 · ×1

AED 15.00

Out of stock

jumper wires Jumper Wire Assorted Pack 120 Pieces - Male-to-Male, Male-to-Female, Female-to-Female 10cm Ribbon Cables for… DIY-212 · ×1

AED 25.02

In stock

Selected parts AED 100.69

One of each part. Packs (resistor assortment, jumper wires) already hold more than a single build needs. Delivery is AED 20, free on orders AED 150+.

// Keep going

More from this kit

Next · 02 →MAX30102 raw optical waveform

Basics 02

MAX30102 raw optical waveform

Use optical mode to stream raw red and infrared samples. Compare no-finger, lightly placed fingertip, firm pressure, ambient-light, and motion conditions. Treat every nu…

Uses

ESP32U MAX30102 breadboard jumper wires

Parts, guide & add to cart →

Basics 03

Experimental optical pulse interval

Observe how the beat detector estimates pulse intervals only when the infrared signal exceeds a provisional quality threshold. Compare stable and moving fingers and expl…

Uses

ESP32U MAX30102 optional OLED breadboard jumper wires

Parts, guide & add to cart →

Basics 04

AD8232 leads-off logic

Keep electrodes off the body and test the LO+ and LO- lines by connecting and disconnecting the supplied lead cable as permitted by its documentation. Verify that the fi…

Uses

ESP32U AD8232 breadboard jumper wires

Parts, guide & add to cart →

All projects →