Picking the cheapest parts for a working prototype
With the software taking shape, it was time to order parts. My goal was the cheapest setup that could honestly prove the idea.
No Raspberry Pi after all
The early plan used a Raspberry Pi. For a product, though, a Pi brings an SD card that can wear out and a full operating system to maintain. The Adafruit MatrixPortal S3 is a small board built to drive LED panels, with Wi-Fi built in and nothing to install but one program. It's cheaper, simpler, and harder to break.
The parts
- Adafruit MatrixPortal S3, the board that runs the display.
- A 128 by 64 LED panel with 2.5 mm dot spacing, about 320 by 160 mm. That's enough dots for card art, a name, and a price at once.
- A 5 volt, 3 amp USB-C power adapter.
- A small Wi-Fi antenna. The board I could get had an antenna connector instead of a built-in antenna, and Adafruit's own antenna was sold out, so I found a compatible one elsewhere.
Then came the hardest part of hardware: waiting for shipping.