Built
Habit
Keychain
The Goal
Create a hardware keychain that helps with habit tracking — integrated with an app. Physical buttons, real-time data, something you carry with you every day.
Video / Photos
Process
Built something very similar to a button matrix connected to an ESP32 with WiFi
Started with an electrical schematic, then tested with smaller buttons on a breadboard
Moved to a perfboard — this is where things got messy
The Mistake
Did not account for soldered wires and plan for them in advance. Everything ended up all over the place, making it nearly impossible to isolate errors. Had to redo the whole board.
Why It's Paused
Getting the app integration right requires FPGA design — which I haven't learned yet. ECE 270 (Fall 2026, hopefully) covers exactly this. Shall be continued.
In Progress
Skillsets Formed
Top 3 Learnings
You don't know what you don't know until you don't know. The FPGA gap only showed up once I was deep in — there's no way to plan for unknown unknowns except to stay curious and ask more people earlier.
Unsoldering is worse than spending 2 extra hours planning better. Map your wire routing before you touch a soldering iron.
Do not panic when you don't know something. You are the source of wisdom — shaking that is only time-ineffective.
Mental Note
Personal reminder
Do not panic when you don't know. You are the source of wisdom, shaking that is ONLY time-ineffective.
Grateful For
Potential Improvements
Some sort of interactive Tamagotchi integration — ambitious but conceptually very cool.