Pocket C6

About the project

Inspiration

Pocket C6 started with a simple question: Can a tiny ESP32-C6 development board become a genuinely useful pocket companion?

The board has a small touchscreen, motion sensor, Wi-Fi, Bluetooth, and a bright LCD. Instead of building just another sensor demo, we wanted to combine these capabilities into one cohesive, interactive device that feels more like a miniature personal computer.

What it does

Pocket C6 is a compact touchscreen companion featuring:

A landscape clock with automatic time synchronization
Four-way physical orientation support
Touch gestures for navigation
Calendar with month browsing
Hangzhou weather and five-day forecasts
Notification and widget pages
BLE mouse and keyboard mode
Touchpad gestures, scrolling, right-click, double-click, and drag selection
Shake-controlled dice and rock-paper-scissors games
Lock mode with reduced frame rate and automatic dimming
Chinese text rendering optimized for the small display
Smooth scroll and transition animations

How we built it

The project is written in Rust and runs directly on the ESP32-C6 using ESP-IDF.

The main architecture consists of:

A Rust application layer for state management and services
LVGL for the graphical user interface
Custom SPI display driver for the JD9853 LCD
I²C drivers for the AXS5106L touch controller and QMI8658 IMU
Bluetooth HID services for mouse and keyboard functionality
Wi-Fi and SNTP for connectivity and time synchronization
A domestic weather API for Hangzhou forecasts
Host-side Rust model tests for gesture, calendar, orientation, and game logic

The UI is organized around pages and applications. Touch gestures control navigation, while individual apps can temporarily take ownership of gestures for focused interactions such as touchpad control or games.

Challenges we ran into

The biggest challenge was adapting every interaction to a 172×320 display. Text, icons, calendars, weather cards, and application tiles all had to remain readable without wasting screen space.

Other challenges included:

Correctly mapping touch coordinates across four physical orientations
Avoiding conflicts between screen gestures and touchpad gestures
Making two-finger scrolling and right-click reliable
Improving cursor smoothness despite limited touch sampling
Rendering Chinese characters consistently with a compact embedded font
Controlling LCD brightness and frame rates to reduce heat
Handling the board’s unusual pinout and shared SPI/I²C buses
Designing safe BOOT-button exit flows that prevent accidental app exits
Working around certificate verification issues with external weather services

Accomplishments that we're proud of

We are proud that Pocket C6 evolved from a hardware test program into a small, coherent operating environment.

The most satisfying achievements are:

A complete LVGL interface running on the ESP32-C6
Reliable BLE touchpad, mouse, and keyboard interactions
Automatic screen rotation based on physical orientation
Smooth, gesture-driven navigation
Usable Chinese UI text on a very small screen
Low-power lock mode with automatic brightness reduction
Multiple interactive applications sharing one consistent UI model
Host-testable Rust logic for hardware-independent behavior

What we learned

We learned that embedded UI development is a balance between hardware constraints and interaction design. A feature that is trivial on a phone can require careful sampling, state tracking, coordinate transforms, and power management on a microcontroller.

We also learned the value of separating pure application logic from hardware drivers. By keeping gesture recognition, calendar calculations, orientation classification, and game rules testable on a desktop, we could iterate much faster and reduce regressions.