Feat: Initial support for LILYGO T3S3 E-Paper

[kevinferrare]

Summary

Adds support for the LilyGo T3S3 E-Paper board (ESP32-S3 + SX1262), with five build configurations:

• Repeater: MeshCore repeater controlled through the USB serial CLI.
• Room Server: MeshCore room server with room password support.
• Companion USB: Companion target using the ESP32 USB serial interface.
• Companion BLE: BLE companion target compatible with the MeshCore companion application.
• Terminal Chat: Secure chat target for direct terminal use.

Hardware

https://lilygo.cc/en-us/products/ts-s3-epaper

Tested on:

• LilyGo T3-S3 (ESP32-S3), 4 MB flash, PSRAM
• SX1262 LoRa transceiver
• 2.13" e-paper display (GxEPD2, black & white)
• Onboard user button

LoRa SPI

• SCK: GPIO 5
• MISO: GPIO 3
• MOSI: GPIO 6
• NSS: GPIO 7, DIO1: GPIO 33, BUSY: GPIO 34

DIO2 is used as the RF switch control, with TCXO voltage set to 1.8V and current limit 140 mA.

Display SPI

Dedicated SPI bus for the e-paper panel (CS: GPIO 15, DC: GPIO 16, RST: GPIO 47, BUSY: GPIO 48, MOSI: GPIO 11), independent from the LoRa SPI pins.

Build targets

LilyGo_T3S3_epaper_repeater

Standard MeshCore repeater with USB serial CLI and OTA support.

LilyGo_T3S3_epaper_room_server

Room server configuration with room/admin password support.

LilyGo_T3S3_epaper_companion_radio_usb

Companion configuration using the USB serial interface.

LilyGo_T3S3_epaper_companion_radio_ble

Companion configuration using the ESP32 BLE interface.

LilyGo_T3S3_epaper_terminal_chat

Minimal secure chat target for direct terminal use.

Scope

This target adds baseline LilyGo T3S3 E-Paper support with display and user button, using the existing GxEPDDisplay helper and MomentaryButton input handling.