LILYGO T-Display Bar

Overview

The LILYGO T-Display Bar is a narrow-form-factor development board designed for bar-style display applications such as smart watches, fitness trackers, instrument panels, and IoT dashboards. Its defining feature is the 2.25-inch IPS LCD with a 76x284 pixel resolution in a tall, slender aspect ratio, making it ideal for scrolling text, vertical meters, and sidebar UI designs.

The board is powered by the ESP32-S3R8, which integrates 8MB of PSRAM directly into the package alongside the dual-core Xtensa LX7 processor. This provides sufficient memory for LVGL-based UIs, animated graphics, and sensor data buffering. The 16MB external flash holds firmware, assets, and local data logs.

Key features:

• 2.25-inch IPS LCD display, 76x284 pixels, bar form factor
• BHI260AP AI-powered 6-axis IMU for gesture and motion detection
• PCF8563 RTC for accurate timekeeping independent of Wi-Fi NTP
• BQ25896 Li-ion/LiPo smart charger with power path management
• BQ27220 fuel gauge for precise battery state-of-charge reporting
• Onboard buzzer and TF (microSD) card slot
• 50 GPIO pins exposed for peripherals
• Wi-Fi 802.11 b/g/n and Bluetooth 5 LE

The BHI260AP IMU includes an embedded AI coprocessor for sensor fusion, step counting, gesture recognition, and activity classification — all running independently of the main CPU. Combined with the BQ25896 charger and BQ27220 fuel gauge, the T-Display Bar provides a complete wearable platform with power management handled in hardware.

Firmware Compatibility

• Arduino: Supported via the arduino-esp32 package. Use ESP32S3 Dev Module as the board target with PSRAM set to OPI PSRAM. LilyGO provides Arduino examples for the display, IMU, RTC, and power management in the GitHub repository.
• ESP-IDF: Full support with native SPI display drivers, I2C peripheral access for BHI260AP/PCF8563/BQ25896/BQ27220, and LVGL integration.
• PlatformIO: Works with the espressif32 platform. Specify the board as esp32-s3-devkitc-1 and configure PSRAM as OPI.

Flashing Guide

1. Connect the T-Display Bar to your computer via USB-C cable.
2. The board should appear as a serial device automatically.
3. If it does not enter download mode, hold BOOT 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 OPI PSRAM (8MB), and set Flash Size to 16MB.
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 to boot into the new firmware.
8. Consult the GitHub repository for pin definitions, display driver setup, and example sketches.