T-Beam BPF Quick Start

Required Libraries

Library	Version	Source
RadioLib	Latest	GitHub
TinyGPSPlus	Latest	GitHub
XPowersLib	Latest	GitHub

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Arduino

PlatformIO (Recommended)

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

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

3. Open platformio.ini and uncomment the T-Beam-BPF environment under default_envs
4. Uncomment one src_dir = xxxx line (only one active at a time)
5. Click ✓ to build, connect via USB-C, click → to upload

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Arduino IDE

1. Install ESP32 Board Support

1. Open Arduino IDE → File → Preferences
2. Add to "Additional Board Manager URLs":

   https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json

3. Go to Tools → Board → Boards Manager, search esp32, install esp32 by Espressif Systems

2. Install Libraries

Copy all folders from the project lib/ to your Arduino libraries directory.

3. Board Settings

Setting	Value
Board	ESP32S3 Dev Module
Upload Speed	921600
USB CDC On Boot	Enabled
CPU Frequency	240 MHz (WiFi)
Flash Size	16 MB (128Mb)
Partition Scheme	16M Flash (3MB APP/9.9MB FATFS)
PSRAM	OPI PSRAM

4. Upload

In utilities.h, uncomment LILYGO_T_BEAM_S3_BPF, then click Upload.

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Peripheral Examples

LoRa (SX1262 + BPF — RadioLib)

The onboard Band Pass Filter (BPF) is always in the RF path. No extra configuration is needed — just use RadioLib normally.

#include <RadioLib.h>

#define LORA_CS    10
#define LORA_IRQ   1
#define LORA_RST   17
#define LORA_BUSY  2

SX1262 radio = new Module(LORA_CS, LORA_IRQ, LORA_RST, LORA_BUSY);

void setup() {
    Serial.begin(115200);
    int state = radio.begin(915.0, 125.0, 9, 7, RADIOLIB_SX126X_SYNC_WORD_PRIVATE, 22);
    if (state != RADIOLIB_ERR_NONE) {
        Serial.printf("LoRa init failed: %d\n", state);
    }
}

void loop() {
    int state = radio.transmit("Hello T-Beam BPF");
    Serial.printf("TX state: %d\n", state);
    delay(2000);
}

GPS (L76K — TinyGPSPlus)

#include <TinyGPSPlus.h>
#include <HardwareSerial.h>

#define GPS_RX  9
#define GPS_TX  8

TinyGPSPlus gps;
HardwareSerial GPSSerial(1);

void setup() {
    Serial.begin(115200);
    GPSSerial.begin(38400, SERIAL_8N1, GPS_RX, GPS_TX);
}

void loop() {
    while (GPSSerial.available()) gps.encode(GPSSerial.read());
    if (gps.location.isUpdated()) {
        Serial.printf("Lat: %.6f  Lon: %.6f\n", gps.location.lat(), gps.location.lng());
    }
}

PMU (AXP2101 — XPowersLib)

#include <XPowersLib.h>

XPowersAXP2101 PMU;

void setup() {
    Serial.begin(115200);
    Wire.begin();
    if (!PMU.begin(Wire, AXP2101_SLAVE_ADDRESS)) {
        Serial.println("PMU init failed");
        return;
    }
    Serial.printf("Battery voltage: %u mV\n", PMU.getBattVoltage());
    Serial.printf("Charging: %s\n", PMU.isCharging() ? "Yes" : "No");
}

void loop() {}

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FAQ

Q: What is the BPF filter for?
A: The Band Pass Filter (BPF) reduces out-of-band harmonics and interference from the high-power LoRa transmitter, improving spectral purity and regulatory compliance.

Q: Upload keeps failing?
A: Hold BOOT, press and release RST, then release BOOT to enter download mode.