LilyGo-LoRa-Series/docs/en/t3_s3_sx1280pa/t3_s3_sx1280pa.md

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<h1 align = "center">🌟LilyGo T3 S3 SX1280PA🌟</h1>

## Overview

* This page introduces the hardware parameters related to `LilyGo T3 S3 SX1280PA`

### Notes on use

1. This version does not have BMS, please use a lithium-ion battery with battery protection function
2. Please be sure to connect the antenna before transmitting, otherwise it is easy to damage the RF module

### Product

| Product    | SOC           | Flash         | PSRAM         |
| ---------- | ------------- | ------------- | ------------- |
| [T3-S3][1] | ESP32-S3FH4R2 | 4MB(Quad-SPI) | 2MB(Quad-SPI) |

[1]: https://www.lilygo.cc/products/t3s3-v1-0?variant=42586879688885 "T3-S3"

### 📍 Pins Map

| Name                   | GPIO NUM                  | Free |
| ---------------------- | ------------------------- | ---- |
| Uart1 TX               | 43(External QWIIC Socket) | ✅️    |
| Uart1 RX               | 44(External QWIIC Socket) | ✅️    |
| QWIIC Socket IO10*     | 10(External QWIIC Socket) | ❌    |
| QWIIC Socket IO21*     | 21(External QWIIC Socket) | ❌    |
| SDA                    | 18                        | ❌    |
| SCL                    | 17                        | ❌    |
| OLED(**SSD1306**) SDA  | Share with I2C bus        | ❌    |
| OLED(**SSD1306**) SCL  | Share with I2C bus        | ❌    |
| SD CS                  | 13                        | ❌    |
| SD MOSI                | 11                        | ❌    |
| SD MISO                | 2                         | ❌    |
| SD SCK                 | 14                        | ❌    |
| LoRa(**SX1280**) SCK   | 5                         | ❌    |
| LoRa(**SX1280**) MISO  | 3                         | ❌    |
| LoRa(**SX1280**) MOSI  | 6                         | ❌    |
| LoRa(**SX1280**) RESET | 8                         | ❌    |
| LoRa(**SX1280**) DIO1  | 9                         | ❌    |
| LoRa(**SX1280**) BUSY  | 36                        | ❌    |
| LoRa(**SX1280**) CS    | 7                         | ❌    |
| LoRa(**SX1280**) TX    | 10                        | ❌    |
| LoRa(**SX1280**) RX    | 21                        | ❌    |
| Button1 (BOOT)         | 0                         | ❌    |
| Battery ADC            | 1                         | ❌    |
| On Board LED           | 37                        | ❌    |

* QWIIC IO10/IO21 GPIOs are already connected to the Radio TX/RX Pin and cannot be used.

### 🧑🏼‍🔧 I2C Devices Address

| Devices              | 7-Bit Address | Share Bus |
| -------------------- | ------------- | --------- |
| OLED Display SSD1306 | 0x3C          | ✅️         |

### ⚡ Electrical parameters

| Features             | Details |
| -------------------- | ------- |
| 🔗USB-C Input Voltage | 5V      |
| ⚡Charge Current      | 500mA   |
| 🔋Battery Voltage     | 3.7V    |

### Button Description

| Channel | Peripherals                    |
| ------- | ------------------------------ |
| BOOT    | Boot mode button, customizable |
| RST     | Reset button                   |

### LED Description

* CHG LED

| LED State | Details               |
| --------- | --------------------- |
| On        | Battery charging      |
| Off       | Battery Full          |
| Blink     | Battery not connected |

* User LED

1. The LED is connected to ESP32 GPIO37, and the LED is turned on or off by writing a high or low level

### RF parameters

| Features            | Details                |
| ------------------- | ---------------------- |
| RF  Module          | SX1280                 |
| Frequency range     | 2400 ~ 2500MHz         |
| Transfer rate(LoRa) | 0.476 ～ 202 Kbps      |
| Transfer rate(FSK)  | 0.125 ～ 20000 Kbps    |
| Transfer rate(FLRC) | 260 ～ 1300 Kbps       |
| Modulation          | LoRa 、 FLRC 、 (G)FSK |

### Frequently asked questions

1. When the module turns on PA (transmit) / LNA (receive) data, the module's RX / TX two input pins need to be set. The state truth table is shown in the table below. Setting errors will result in failure to send and receive data normally.

| TX PIN | RX PIN | Radio Status      |
| ------ | ------ | ----------------- |
| 1      | X      | PA ( TX active )  |
| 0      | 1      | LNA ( RX active ) |

2. Recommended that the software controls the 1280 chip to output 2~5dbm, so that the entire module will output 20dbm power; When the output of the 1280 chip is higher than 2dbm, the output power of the entire module is only 20dbm; When the output of the 1280 chip is higher than 5dbm, the output power of the entire module is only 20dbm, but if 5dbm is given to the FEM, it will damage the FEM chip (the maximum input allowed by the FEM is 5dbm) .If the output of the 1280 chip is lower than 2dbm, the output power of the entire module is within 20dbm.
3. SX1280 output power setting cannot be greater than 2~5dbm, otherwise the FEM chip may be damaged. Setting 3dbm already has 20dmb output power

#### Resource

* [T3_S3_V1.2 schematic](../../../schematic/T3_S3_V1.2.pdf)
* [T3_S3_V1.3 schematic](../../../schematic/T3_S3_V1.3.pdf)
* [SX1280 datasheet](https://www.semtech.cn/products/wireless-rf/lora-connect/sx1280)