T3-S3 Quick Start

Required Libraries

Library	Version	Source
RadioLib	Latest	GitHub
U8g2	Latest	Arduino Library Manager

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Arduino

PlatformIO (Recommended)

1. Install VS Code with the PlatformIO IDE extension
2. Clone the repository:

   git clone https://github.com/Xinyuan-LilyGO/LilyGo-LoRa-Series.git

3. Open the project, select the environment matching your LoRa module variant in platformio.ini
4. Click ✓ to build, connect via USB-C, then click → to upload

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Arduino IDE

Board Settings

Setting	Value
Board	LilyGo T3-S3
Board Revision	Select per LoRa module (SX1262 / SX1276 / SX1280 etc.)
Upload Speed	921600
USB Mode	Hardware CDC and JTAG
USB CDC On Boot	Enabled
CPU Frequency	240 MHz (WiFi)
Flash Mode	QIO 80 MHz
Flash Size	4MB (32Mb)
Partition Scheme	Default 4MB with spiffs
PSRAM	QSPI PSRAM

Steps

1. Install Arduino IDE and add ESP32 board support: https://espressif.github.io/arduino-esp32/package_esp32_index.json
2. In Board Manager, search for esp32 by Espressif Systems and install
3. Clone the LilyGo-LoRa-Series repo and open an example sketch
4. Select LilyGo T3-S3 and set the Board Revision to match your module
5. Click Upload

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Peripheral Examples

LoRa (SX1262)

#include <RadioLib.h>

// T3-S3 SX1262: CS=7, IRQ=33, RST=8, BUSY=34
SX1262 radio = new Module(7, 33, 8, 34);

void setup() {
  Serial.begin(115200);
  int state = radio.begin(915.0);
  if (state != RADIOLIB_ERR_NONE) {
    Serial.print("Radio init failed: "); Serial.println(state);
    while (true);
  }
  radio.setOutputPower(22);
  Serial.println("SX1262 ready");
}

void loop() {
  int state = radio.transmit("Hello T3-S3");
  if (state == RADIOLIB_ERR_NONE) Serial.println("Sent OK");
  delay(2000);
}

OLED Display (SSD1306)

#include <U8g2lib.h>
#include <Wire.h>

// SSD1306 128×64 I2C, SDA=18, SCL=17
U8G2_SSD1306_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0, U8X8_PIN_NONE);

void setup() {
  Wire.begin(18, 17);
  u8g2.begin();
}

void loop() {
  u8g2.clearBuffer();
  u8g2.setFont(u8g2_font_ncenB08_tr);
  u8g2.drawStr(0, 20, "T3-S3 Ready");
  u8g2.sendBuffer();
  delay(1000);
}

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Notes

• LoRa variant: SX1262 / SX1276 / SX1278 (Sub-GHz) or SX1280 (2.4 GHz) — set the correct Board Revision or #define in utilities.h
• PSRAM: QSPI PSRAM — select QSPI PSRAM in Arduino IDE
• Meshtastic: This board is Meshtastic compatible; flash via the Meshtastic web flasher or CLI
• GPIO10/GPIO21: On SX1276/78 variants, these are tied to DIO3/DIO4; remove the resistors to free them for general use

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FAQ

Q: Cannot upload — port not found? A: Ensure USB CDC On Boot is set to Enabled. If it was previously disabled, hold BOOT and press RST to enter download mode.

Q: Which LoRa module do I have? A: Check the markings on the RF module or refer to your order. SX1280 modules support 2.4 GHz; SX1262/76/78 support Sub-GHz bands.