# CircuitMess ClockStar 2.0

> DIY smartwatch kit powered by ESP32 with ST7735S display, 6-axis IMU, Bluetooth connectivity, and programmable via CircuitBlocks visual coding environment.

## Quick Facts

- **Brand:** circuitmess
- **Board Type:** diy-kit
- **Price:** ~$140
- **Product Readiness:** consumer
- **CPU:** Xtensa LX6 dual-core @ 240MHz, FPU
- **CPU Architecture:** Xtensa LX6
- **CPU Cores:** 2
- **RAM:** 520KB SRAM
- **Flash:** 4MB
- **USB:** Micro-USB
- **Power:** LiPo battery
- **Operating Voltage:** 3.3V
- **Antenna:** Built-in PCB antenna
- **Display:** 1.44" TFT 128×128

## Connectivity

- **Wifi:** 802.11 b/g/n
- **Bluetooth:** BLE 4.2

## Open Source

- **Firmware:** Yes
- **Schematics:** No
- **PCB Layout:** No

## Compatible Firmware

arduino, circuitblocks, esp-idf

## Use Cases

- smart-watch
- wearable
- stem-education
- educational-platform

## Components

- **ESP32** (mcu): Espressif ESP32 dual-core Xtensa LX6 microcontroller running at 240MHz with WiFi 802.11 b/g/n and Bluetooth 4.2 LE. 520KB SRAM, 4MB flash. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.espressif.com%2Fsites%2Fdefault%2Ffiles%2Fdocumentation%2Fesp32_datasheet_en.pdf&ref=openhardware.directory&product=circuitmess-clockstar-2-0&source=md-export)
- **ST7735S** (display-driver): Sitronix ST7735S TFT LCD controller driving a 128×128 pixel color display over SPI interface at 40MHz. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.displayfuture.com%2FDisplay%2Fdatasheet%2Fcontroller%2FST7735.pdf&ref=openhardware.directory&product=circuitmess-clockstar-2-0&source=md-export)
- **LSM6DS3TR-C** (imu): STMicroelectronics LSM6DS3TR-C 6-axis IMU providing 3D accelerometer and 3D gyroscope data over I2C. Features wrist tilt detection, tap recognition, and significant motion detection for smartwatch use. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.st.com%2Fresource%2Fen%2Fdatasheet%2Flsm6ds3tr-c.pdf&ref=openhardware.directory&product=circuitmess-clockstar-2-0&source=md-export)

## Protocols

- **SPI** (SPI2): SCK: GPIO16, MOSI: GPIO17, DC: GPIO5, RST: GPIO18
- **I2C**: SDA: GPIO26, SCL: GPIO25

## GPIO Map

| Pin | Name | Type | Functions |
|-----|------|------|-----------|
| GPIO14 | Button DOWN | — | digital-input |
| GPIO15 | Button UP | — | digital-input |
| GPIO27 | Button SELECT | — | digital-input |
| GPIO39 | Button ALT | — | input-only |
| GPIO21 | RGB LED Red | — | digital-output, pwm |
| GPIO22 | RGB LED Green | — | digital-output, pwm |
| GPIO23 | RGB LED Blue | — | digital-output, pwm |
| GPIO4 | Backlight | — | digital-output, pwm |
| GPIO2 | Buzzer | — | digital-output, pwm |
| GPIO36 | Battery ADC | — | input-only, adc |
| GPIO19 | Charge Detect | — | digital-input |
| GPIO35 | IMU INT1 | — | input-only |
| GPIO34 | IMU INT2 | — | input-only |
| GPIO26 | I2C SDA | I2C | digital-input, digital-output |
| GPIO25 | I2C SCL | I2C | digital-input, digital-output, dac |
| GPIO16 | TFT SCK | SPI | digital-output |
| GPIO17 | TFT MOSI | SPI | digital-output |
| GPIO5 | TFT DC | — | digital-output |
| GPIO18 | TFT RST | — | digital-output |

## Description

## Overview

The CircuitMess ClockStar 2.0 is a DIY smartwatch kit that teaches electronics assembly and programming through hands-on building. Powered by an ESP32 dual-core microcontroller, it features a 128×128 color TFT display, a 6-axis IMU with accelerometer and gyroscope, Bluetooth connectivity for pairing with smartphones, and an RGB notification LED.

Assembly takes approximately one hour with step-by-step instructions and 100+ photos. Once built, the watch displays time, date, alarms, and stopwatch functions. It connects to the CircuitMess mobile app to mirror smartphone notifications.

The watch is fully programmable through CircuitBlocks, a visual block-based coding environment that generates Arduino-compatible code. Users can create custom watch faces, animations, and interactive applications like a gyroscope-controlled balance ball game. Advanced users can program directly in C++ using the Arduino IDE or ESP-IDF framework.

## Where to Buy

- [CircuitMess](https://openhardware.directory/r?to=https%3A%2F%2Fcircuitmess.com%2Fproducts%2Fclockstar-2-0&ref=openhardware.directory&product=circuitmess-clockstar-2-0&source=md-export) — €129.00

## Resources

- [product](https://openhardware.directory/r?to=https%3A%2F%2Fcircuitmess.com%2Fproducts%2Fclockstar-2-0&ref=openhardware.directory&product=circuitmess-clockstar-2-0&source=md-export)
- [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2FCircuitMess%2FClockstar-Firmware&ref=openhardware.directory&product=circuitmess-clockstar-2-0&source=md-export)

## Tags

`circuitmess`, `smartwatch`, `diy-kit`, `esp32`, `stem`, `wearable`

## Images

![CircuitMess ClockStar 2.0](https://nbg1.your-objectstorage.com/openhardware-directory/entities/circuitmess-clockstar-2-0/87e9f4f4074c.webp)
![CircuitMess ClockStar 2.0](https://nbg1.your-objectstorage.com/openhardware-directory/entities/circuitmess-clockstar-2-0/f5de99da3874.webp)
![CircuitMess ClockStar 2.0](https://nbg1.your-objectstorage.com/openhardware-directory/entities/circuitmess-clockstar-2-0/a10e3070d026.webp)

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