Mara X Display
ESPHome firmware that puts a live brew timer, recovery-shaded temperature chart and machine status on a 3.5″ touchscreen wired to your Lelit Mara X.
Plug the ESP32-S3 board into USB, click Install, and pick the serial port. After flashing you'll be prompted for WiFi credentials in the browser via Improv-Serial. If the prompt doesn't appear (the serial handshake can miss its window on a slow boot), the firmware also accepts Improv over BLE — pair from a phone app or Chrome's Web Bluetooth.
Hobby project. Not affiliated with Lelit. Still looking for a nice display enclosure and a clean PCB harness for the UART + power wiring — open an issue if you've designed something for this combo.
What you get
- Steam, HX and target temperatures live off the Mara X UART
- Shot timer at 100 ms precision, value persists after the pump stops
- Auto-switching chart: 1 s / 50 s window while brewing, 15 s / 15 min window otherwise
- Shaded brew window and 90 s recovery bands drawn behind the trace
- Demo mode with synthetic machine cycles for testing without a connected machine
- Home Assistant integration over the ESPHome API — fire a notification when the brew group's up to temperature, log shots, whatever you like
Hardware
- All-in-one ESP32-S3 board with 3.5″ 480 × 320 QSPI touchscreen — tested on the
jc3248w535 - Sold under generic search terms like "ESP32 S3 3.5 inch LCD Development Board 480x320 Display"
- AXS15231 touch controller, octal PSRAM @ 80 MHz
- UART tap into the Mara X service connector (9600 baud, inverted logic)