Hardware & technical reference
The reference build. Panel size and chain length are set at compile time, so other configurations are possible.
Controller
- MCU
- ESP32-S3-WROOM-1 (module
esp32-s3-devkitc-1) - Flash
- 16 MB (quad)
- PSRAM
- 8 MB (octal)
- USB
- onboard CH343 USB-UART bridge for flashing and serial (115200 baud)
- Web server
- HTTP on port 80; the interface is bundled into the firmware
Panel
- Type
- HUB75 RGB LED matrix
- Resolution
- 64×32 per module (default); 1/16 scan
- Chain
- 1 module (configurable)
- Driver chip
- FM6126A
- Refresh
- ~120 Hz, double-buffered
- Gamma
- 2.2 (per-panel calibration, set at build time)
Power
Give the panel its own 5 V supply, sized for it — a 64×32 HUB75 panel at full white draws several amps. The controller's USB port is for data and flashing, not for running the panel. Undervoltage shows up as an all-red or washed-out display, not as an obvious power fault.
Configuration limits
| Thing | Limit |
|---|---|
| Views | 30 |
| Elements per view | 6 |
| Custom data sources | 8 |
| Headers per data source | 8 |
| Minimum poll interval | 10 seconds |
| API response body | 8 KB |
| Custom animation frames per view | 10 |
| Painted pixels across one view's animation | 2000 |
| Imported GIF frames | 60 |
Network & privacy
- The interface is served by the device over your LAN, on plain HTTP.
- No authentication in this build — anyone on the network can open it.
- No cloud, no account. The device only makes outbound requests to the APIs you configure.
- No mDNS: reach the device by the IP address shown on the panel, not a
.localname.