10/7/2025 - Suckyducky — Learning & Exploration Journal

Suckyducky — Learning & Exploration Journal

Days: 1–3

Total Time Logged: ~20 hours

Phase: Research, Understanding, and Setup

Status: Still figuring things out, hands-on work starts tomorrow 🚀

🧠 Day 1 — Understanding the Core Idea (6 hours)

Focus: Researching how Rubber Ducky works and understanding microcontroller behavior.

Today was about going back to the roots — what actually is a USB Rubber Ducky, and how can I replicate that logic using open hardware?

I started with the original Hackster guide by Maninderbir Gulshan. I spent most of the time trying to break it down into smaller mental blocks:

• How the MK20DX128 microcontroller handles USB HID emulation.
  
• What it means for a device to “pretend” to be a keyboard.
  
• How payloads are stored, parsed, and executed.
  
• The firmware logic — reading text-based payloads and converting them to keypresses.

I went through multiple YouTube breakdowns of HID devices and looked into Teensy’s HID libraries. I didn’t write any code yet, but I started noting what will be essential for the “Suckyducky” identity — safety, openness, modularity.

It’s fascinating how simple hardware can be so powerful when paired with creative firmware.

By the end of the day, I was convinced that I’m not just building another clone — I’m building a controlled, transparent, and educational version.

Reflection:

It’s strange how a simple concept — pretending to be a keyboard — opens doors to deep ethical and technical debates. I want Suckyducky to represent the responsible side of curiosity.

🔩 Day 2 — Exploring the Hardware Side (7 hours)

Focus: Components, schematic basics, and KiCad setup.

Today I opened KiCad for the first time for this project. My goal was to get comfortable with:

• Creating a basic schematic (MCU + USB + LED + switch).
  
• Understanding how USB D+ and D− lines connect to the microcontroller.
  
• How power regulation and decoupling capacitors work.
  
• Identifying each component in the Hackster BOM and mapping it to modern equivalents.

I didn’t draw a full schematic yet, but I practiced placing footprints and running ERC checks.

I also researched 3D printed enclosures, since I want Suckyducky to look professional even in its prototype phase.

Later in the evening, I watched tutorials on how to generate Gerbers and how to simulate trace width for USB signal stability.

This part is challenging — hardware is slower to grasp than code. Still, it’s rewarding when I finally visualize the physical connections in my head.

Reflection:

It feels like I’m finally getting my hands dirty — even if it’s still digital dirt. Hardware design teaches patience; every small wire has meaning.

⚙️ Day 3 — Firmware Concepts & Early Planning (7 hours)

Focus: Firmware logic, payload design, and structure of the code.

I decided to design the firmware architecture before writing any actual code. My goal was to think like an engineer — not just a coder.

Main blocks I designed (on paper and notes):

1. HID Engine: the part that sends keystrokes.
   
2. Payload Loader: reads files from SD or flash memory.
   
3. Safety Layer: checks for config switch before execution.
   
4. LED & Debug Layer: communicates device state.
   

I studied how Teensy handles USB keyboard libraries and realized I can reuse that framework for Suckyducky’s base.

Then, I started drafting a simple “Hello World” payload format — something like: