My First Real Solder Job: A Desktop Game of Life
While waiting for my Synapse DMX PCBs to arrive from JLCPCB, I wanted to keep my hands busy with a smaller project. I had some Teensy 4.0s lying around and found these cheap 0.96" OLED displays on Amazon — the ones with the yellow strip at the top and blue for the rest. Perfect excuse to finally learn to solder.
The Idea
Conway's Game of Life on a tiny screen. Classic cellular automata, 128x48 pixels of evolving chaos sitting on my desk. The yellow portion of the display shows the title, and all the action happens in the blue area below. Two buttons: one to reseed the simulation, one to toggle between 1x1 and 2x2 pixel cells.
The Build
The software came together pretty quick — Teensy 4.0 is total overkill for this but it's what I had. Bit-packed buffers to fit the grid in memory, toroidal wrapping so patterns flow off one edge and appear on the other, standard Conway rules. The code runs flat out with no delay, just computing generations and pushing pixels as fast as possible.
The hardware is where I actually learned something. I've breadboarded plenty of stuff before, but this was my first time transferring a prototype to perfboard with actual solder joints.
What I Learned (The Hard Way)
My first attempt was a disaster. I completely fried an OLED screen and melted wires together — just totally butchered it. I was using too much heat, too much solder, moving too fast. When I tested it, everything showed continuity on the multimeter, but VCC, SCL, and SDA were all reading 3.3V. The signal lines shouldn't be sitting at the supply voltage. I had solder bridges everywhere shorting VCC to the adjacent pins. Those OLED header pins are tight. The whole thing was unsalvageable.
My second attempt went much better. I slowed way down and checked connections as I went instead of wiring everything and hoping for the best at the end. The difference was night and day:
- › Less solder than you think you need
- › Inspect every joint before moving to the next one
- › Check for bridges between adjacent pins with the multimeter, not just continuity to the destination
- › The view from the back of the board is mirrored — double check which pad is which before wiring
- › Don't rush. Seriously. Just don't.
The actual soldering technique took some getting used to. Touch the iron to both the pad and the pin, wait for them to heat up, then feed the solder into the joint — not onto the iron. Clean the tip constantly. Let it cool before you move anything.
The Stack
Hardware
- › Teensy 4.0
- › SSD1306 128x64 OLED (I2C)
- › Two tactile buttons
- › Perfboard, 22 AWG solid core wire, 63/37 rosin core solder
Connections
- › 3.3V → OLED VCC
- › GND → OLED GND → Buttons (daisy chained)
- › Pin 18 → OLED SDA
- › Pin 19 → OLED SCL
- › Pin 2 → Seed button
- › Pin 3 → Size toggle button
Was It Worth It?
Absolutely. It's a stupid little desk toy that does nothing useful, but I actually made it. Not just wired it on a breadboard — soldered it, debugged it, destroyed an OLED, started over, and now it works.
More importantly, this gives me way more confidence for when those Synapse PCBs show up. If I can survive janky point-to-point perfboard wiring and live to tell about it, populated PCBs with proper pads and silkscreen labels are going to feel luxurious.