LILYGO T-Mini E-Paper S3

Overview

The LILYGO T-Mini E-Paper S3 combines an ESP32-S3FN4R2 microcontroller with a Semtech SX1262 LoRa radio and a 1.02-inch e-paper display in a compact form factor. The e-paper display uses the GDGDEWG102T4 driver at 128x80 pixel resolution, providing a high-contrast, sunlight-readable readout that consumes zero power when not refreshing — ideal for battery-operated field devices.

The SX1262 supports both 868MHz (EU) and 915MHz (US/AU) frequency bands depending on the variant ordered, enabling long-range LoRa communication over several kilometres in open terrain. When combined with the ESP32-S3's Wi-Fi and Bluetooth, the board can act as a LoRa-to-Wi-Fi gateway, a Meshtastic node, or a standalone sensor display with periodic LoRa uplinks.

Key features:

• ESP32-S3FN4R2 with 4MB flash and 2MB PSRAM in the package
• SX1262 LoRa transceiver (868MHz or 915MHz variant)
• 1.02-inch e-paper display, 128x80 pixels, GDGDEWG102T4 driver
• TF (microSD) card slot for data logging
• 18350 cylindrical battery connector (battery not included)
• USB-C for programming and charging
• Wi-Fi 802.11 b/g/n and Bluetooth 5 LE

The use of the ESP32-S3FN4R2 package — which integrates flash and PSRAM directly — keeps the BOM small and the board compact. The e-paper display retains its last image indefinitely without power, making it suitable for status boards that only update occasionally and need to remain readable during sleep intervals.

Firmware Compatibility

• Arduino: Supported via arduino-esp32. Use ESP32S3 Dev Module. The SX1262 is compatible with the RadioLib and LoRa Arduino libraries. The e-paper display uses the GxEPD2 library with the appropriate driver class for the GDGDEWG102T4 panel.
• ESP-IDF: Native SPI driver for both the SX1262 and the e-paper display. The LilyGO GitHub repository provides ESP-IDF compatible examples.
• PlatformIO: Use the espressif32 platform with esp32-s3-devkitc-1 board target. Include RadioLib and GxEPD2 in lib_deps.
• Meshtastic: The SX1262 radio is compatible with Meshtastic firmware. Flash the standard Meshtastic ESP32-S3 build and configure the SX1262 pins as documented in the GitHub repository.

Flashing Guide

1. Connect the T-Mini E-Paper S3 to your computer via USB-C cable.
2. The board will appear as a serial device.
3. If the device does not enter download mode automatically, hold the BOOT button while pressing RESET, then release BOOT.
4. For Arduino IDE: install the ESP32 board package (v2.x or later), select ESP32S3 Dev Module, set PSRAM to QSPI PSRAM (2MB), and Flash Size to 4MB.
5. For ESP-IDF:

   idf.py -p /dev/ttyUSB0 flash monitor
   

6. For esptool:

   esptool.py --chip esp32s3 --port /dev/ttyUSB0 --baud 921600 write_flash -z 0x0 firmware.bin
   

7. After flashing, press RESET. The e-paper display will show the initial image after the first full refresh cycle.
8. See the GitHub repository for pinout documentation, SX1262 configuration, and complete example sketches.
9. Note: The 18350 battery is not included in the package and must be purchased separately if battery operation is needed.