DriftPad

DriftPad

DriftPad is a custom Hall-effect macropad built around analog magnetic key sensing. The project is designed to support adjustable actuation and release points, rapid-trigger-style behavior, an OLED interface, and rotary encoder input on a custom PCB.

Status: In development. Hardware design is underway and firmware development has started.

Features

• Hall-effect analog key sensing
• Adjustable actuation and release points
• Rapid-trigger-style key behavior
• OLED display for real-time status and configuration
• Rotary encoder input
• Custom PCB design
• Custom 3D-printed enclosure
• Raspberry Pi Pico / RP2040-based firmware development

Project Goals

DriftPad is intended to explore the full design of a custom input device, including:

• PCB schematic and layout design
• Analog Hall-effect sensor integration
• Embedded firmware development
• USB keyboard/HID behavior
• OLED user interface design
• Rotary encoder input handling
• Mechanical enclosure design and prototyping

Repository Structure

DriftPad/
├── firmware/        # PlatformIO firmware project
├── hardware/        # PCB and mechanical design files
├── docs/            # Documentation and diagrams
├── media/           # Photos, renders, and project media
├── README.md
└── LICENSE

Firmware

The firmware is currently being developed with PlatformIO for the Raspberry Pi Pico / RP2040.

firmware/
├── include/
├── lib/
├── src/
├── test/
└── platformio.ini

Planned firmware components include:

• Hall-effect sensor sampling and calibration
• Adjustable actuation thresholds
• Adjustable release thresholds
• Rapid-trigger logic
• Keyboard/HID output
• OLED display control
• Rotary encoder handling
• Profiles and configuration settings

Hardware

The hardware portion of the project includes:

• KiCad schematics
• PCB layout
• Custom footprints and symbols where required
• Manufacturing files
• 3D-printable enclosure parts
• STL and related mechanical design files

A planned organization is:

hardware/
├── kicad/
└── mechanical/
    ├── stl/
    └── step/

Hardware Platform

Current development is based around the Raspberry Pi Pico / RP2040.

The RP2040 will handle:

• Analog sensor acquisition
• Key state processing
• USB HID communication
• OLED updates
• Rotary encoder input
• User configuration

Hall-Effect Key Sensing

Unlike a traditional mechanical keyboard switch that provides a simple digital on/off signal, DriftPad uses Hall-effect sensors to measure the position of each key magnetically.

This allows the firmware to determine key travel continuously and implement features such as:

• User-adjustable actuation distance
• User-adjustable release distance
• Dynamic key reset behavior
• Rapid-trigger-style input

OLED Display

The OLED is intended to provide real-time visual feedback such as:

• Active profile or layer
• Actuation settings
• Key status
• Configuration menus
• Simple graphics and animations

Rotary Encoder

The rotary encoder will provide an additional input method for functions such as:

• Volume control
• Menu navigation
• Profile selection
• Configuration adjustment

Its exact behavior may evolve as the firmware develops.

Development

Firmware development is being done in Visual Studio Code using PlatformIO.

To open the firmware project:

cd firmware
code .

PlatformIO uses the configuration in:

firmware/platformio.ini

Build artifacts generated inside .pio/ are not tracked by Git.

Current Progress

• Project concept and feature planning
• KiCad schematic development
• PCB design
• Mechanical / STL design
• PlatformIO firmware project setup
• Hall-effect sensor firmware
• Sensor calibration system
• Keyboard/HID implementation
• Adjustable actuation logic
• Rapid-trigger logic
• OLED interface
• Rotary encoder integration
• Hardware bring-up and testing
• Final enclosure and assembly
• Performance testing and documentation

Planned Documentation

As development continues, this repository will include additional documentation covering:

• System architecture
• PCB design decisions
• Hall-effect calibration
• Firmware architecture
• Actuation and rapid-trigger algorithms
• Hardware bring-up
• Testing and performance measurements
• Final assembly

License

See LICENSE for licensing information.