PocketVault Devlog #3 – Firmware Foundation & Repository Setup

Today I shifted focus from hardware design to software development and project organization.

With the PCB design complete and enclosure designs in progress, it was time to start building the firmware that will power PocketVault.

Firmware Project Setup

I created the initial PlatformIO project for PocketVault using VS Code.

The project is configured for the RP2040 platform and will eventually support:

• OLED user interface
• Rotary encoder navigation
• USB HID password typing
• Master PIN protection
• Offline password storage

The firmware architecture is kept simple to make future development easier.

Project Structure

To keep the code organized from the beginning, I created separate configuration files for different parts of the project.
Current structure:

PocketVault/
 |── include/
 |      ├── config.h│   
 |      ├── vault.h   
 |      └── settings.h
 |── src/
 |      └── main.cpp
 |── platformio.ini
 |── README.md

File Responsibilities

• config.h → Hardware configuration and firmware settings
• vault.h → Password entry definitions
• settings.h → Future settings menu definitions
• main.cpp → Core application logic

GitHub Repository

I prepared the repository for public development by:

• Creating a README
• Adding a proper .gitignore
• Organizing project files* Preparing documentation
  The goal is to make it easy for anyone to clone the project and build it using PlatformIO.

Documentation

I also created:

• README.md
• BOM.md
• Wiring.md

These documents cover:

• Project overview
• Bill of Materials
• Wiring information
• Build instructions
• Future roadmap

Challenges

One issue encountered was PlatformIO board support.

The Seeed Studio XIAO RP2040 board definition was unavailable in the current PlatformIO installation, so development is temporarily targeting the Raspberry Pi Pico board definition since both use the RP2040 microcontroller.

This allows firmware development to continue while maintaining compatibility with the final hardware.

PocketVault Devlog #2 – Designing the Enclosure

After completing the first PCB revision for PocketVault, I shifted my focus to the physical design of the device. Today was all about creating the enclosure and turning the project into something that actually feels like a finished product though I don’t plan to include it in the first ship because of the complexity

What I Worked On

CAD Design

I created the first CAD model for the PocketVault enclosure.

Component Integration

Using the PCB dimensions as a reference, I designed mounting features for the PCB

Challenges

During the design I faced many problems in it as I did not know to design 3D cad models

PocketVault Devlog #1 – PCB Design Complete

Today was a big step for PocketVault.

What I Worked On

PCB Design

I completed the first PCB revision for PocketVault in KiCad.

The board currently includes:

• Seeed Studio XIAO RP2040
• 128×64 SSD1306 OLED display
• Rotary encoder with push button for navigation
• Mounting holes for enclosure integration
• Custom board outline designed for the PocketVault form factor

Interface Design

The entire user interface will be controlled using a rotary encoder:

• Rotate to navigate menus
• Press to select options
• OLED display for viewing entries and settings

This approach keeps the device compact while avoiding the need for a keyboard or touchscreen.