T-Beam LoRa “Hello” Link (Sender + Receiver) — RadioLib (SX1262, 868 MHz)

A minimal two-device project using two LILYGO T-Beam V1.2 (ESP32 + SX1262) boards to communicate over LoRa in the EU 868 MHz band.

---

What is LoRa (in plain words)?

LoRa is a long-range, low-power radio technology.
Think of it like “walkie-talkies for tiny data”:

• ✅ Works over long distances (often hundreds of meters to kilometers depending on environment)
• ✅ Uses very little power
• ✅ Sends small messages (not suitable for high-speed data like Wi‑Fi)

In this project, LoRa is used to send a simple text message from one board to another.

---

Software Overview

This repository contains one program:

The program uses the RadioLib library to control the SX1262 LoRa radio on the T-Beam.

---

Program Logic (How it works)

This is the ping pong example of radiolib, adapted for T-BEAM as below. The program checks, if a packet was received and prints out data, Signal strength and Signal-to-Noise Ratio. Then it waits a second, and sends itself a message. The initial message is in setup, starting with INITIATING_NODE. When uploading the program, in one of the 2 devices , the line #define INITIATING_NODE must be commented out, then it's clear which device starts the communication.

---

Features

• ✅ Uses EU 868 MHz frequency
• ✅ Uses RadioLib (SX1262 support)

---

Hardware / Components Used

Boards

• 2× LILYGO T-Beam V1.2
  • MCU: ESP32
  • LoRa radio: SX1262
  • GPS: NEO-M8N
  • PMU: AXP2101
  • USB-UART: CH9102
  • Flash: 4MB, PSRAM: 8MB
  • Marking: LILYGO 868/915 MHz Model: LORA32 SX1262

Region / Frequency

• Europe (EU): 868 MHz is used in the code:
  • static const float LORA_FREQ = 868.0;

⚠️ Always follow your local radio regulations (frequency, transmit power, duty cycle).

Dependencies / Libraries Used

• Arduino framework (ESP32)

• RadioLib by Jan Gromeš

  Used to control the SX1262 LoRa radio. In PlatformIO, you typically add:

  lib_deps = jgromes/RadioLib Build & Flash (PlatformIO)

Prerequisites

• Install VS Code

• ✅ Install the PlatformIO extension

• Connect your T-Beam via USB (CH9102 driver may be required depending on your OS)

• Compile & Upload

• Open the sender project and run:

• Build

• Upload

• Monitor (Serial Monitor at 115200 baud) -Repeat for the receiver project.

-Serial Monitor Settings -Baud rate: 115200

Sender output example:

Usage

Future Improvements

• Add deep sleep for low-power battery operation
• Add structured payloads (JSON or binary packets)

Acknowledgements

• RadioLib library by Jan Gromeš and contributors
• LILYGO for the T-Beam hardware platform

License

• This project is licensed under the MIT License. See the LICENSE file for details.

Images

2. 3.