openHASP Touchscreen Panel for T-HMI
An MQTT-driven Home Assistant touchscreen panel for the LILYGO T-HMI using openHASP — define buttons, sliders, and labels via JSON and push UI updates over-the-air without recompiling firmware.
Overview
openHASP turns the LILYGO T-HMI's 2.8-inch resistive touchscreen into a fully configurable Home Assistant control panel. The firmware runs on the ESP32-S3 and communicates with Home Assistant via MQTT, so any automation, entity state, or script can be reflected and triggered from the display.
UI Design Without Code
Panel layouts are defined as pages.jsonl files — one JSON object per line describing buttons, sliders, labels, toggle switches, and media player controls. These files are uploaded to the device's internal storage via the web interface and take effect immediately. Changing a screen layout never requires a firmware recompile. Themes can be applied globally, and pages allow grouping controls (for example, a lighting page, a climate page, a media page).
Build Details
openHASP (962 GitHub stars) has official support for the T-HMI with a dedicated configuration in user_setups/esp32s3/lilygo-t-hmi.ini. Pre-compiled firmware binaries are available for direct flashing. The 16 MB flash and 8 MB PSRAM provide ample headroom for complex multi-page interfaces. The project integrates with Home Assistant, OpenHAB, and Node-RED.
