1. Úvod
The EoRa-S3-900TB is a versatile development board designed by EBYTE, integrating the powerful ESP32-S3FH4R2 chip with a LoRa module. This board is engineered for a wide range of applications requiring Wi-Fi, Bluetooth LE, and LoRa wireless communication capabilities. It features a compact design with essential peripherals for rapid prototyping and testing.
The ESP32-S3 is a low-power MCU system-on-chip (SoC) that supports 2.4 GHz Wi-Fi and Bluetooth LE wireless communication. The chip integrates a high-performance 32-bit LX7 dual-core processor, an ultra-low-power co-processor, Wi-Fi baseband, Bluetooth baseband, RF module, and peripherals up to 240 MHz. The ESP32-S3FH4R2 package includes 384 KB of ROM, 512 KB of SRAM, 16 KB of RTC SRAM, 4 MB of FLASH, and 2 MB of PSRAM.

Obrázek: Úhlový view of the EoRa-S3-900TB Test Board, showcasing its compact form factor and various components.
2. Klíčové vlastnosti
- Procesor: 32-bit LX7 dual-core processor, up to 240 MHz.
- Paměť: Integrated 4 MB FLASH and 2 MB PSRAM.
- Bezdrátové připojení: Supports 2.4 GHz Wi-Fi (IEEE 802.11b/g/n) and Bluetooth LE (Bluetooth 5, Bluetooth mesh).
- Modul LoRa: E22-900MM22S with SX1262 chip, supporting 850 ~ 930 MHz operating frequency and +22 dBm max output power.
- Zobrazit: Integrated 0.96-inch OLED display.
- Skladování: SD card slot for expanded storage.
- Řízení spotřeby: Li-ion battery charging circuit with a rated charging current of 500mA.
- Rozhraní: Type-C interface with USB 2.0 protocol for power and data.
- Anténa: Common antenna for Wi-Fi and Bluetooth.
3. Technické specifikace
| Specifikace | Hodnota |
|---|---|
| Název modelu | EoRa-S3-900TB |
| Značka | EBYTE |
| Rychlost CPU | 240 MHz |
| Kapacita paměti | 6 MB (4MB FLASH + 2MB PSRAM) |
| Technologie připojení | Bluetooth, WiFi |
| Protokoly Wi-Fi | IEEE 802.11b/g/n (20 MHz and 40 MHz bandwidths) |
| Datová rychlost Wi-Fi | Up to 150 Mbps (1T1R mode) |
| Bluetooth LE Rates | 125 Kbps, 500 Kbps, 1 Mbps, 2 Mbps |
| Frekvence LoRa | 850 ~ 930 MHz |
| LoRa Max Output Power | +22 dBm |
| OLED Display Size | 0.96 palců |
| Nabíjecí proud baterie | 500mA (rated) |
| Rozhraní | Type-C (USB 2.0) |
4. Obsah balení
The EoRa-S3-900TB package typically includes the following components:
- EoRa-S3-900TB Development Board (with integrated Type-C interface, E22-900MM22S LoRa module, 0.96-inch OLED display, SD card slot, Li-ion battery charging circuit, and power circuit)

Image: The product packaging box, displaying manufacturer details and certifications.
5. Hardware Components and Pinout
The EoRa-S3-900TB board is designed with various accessible components and GPIO pins for development and testing. Below are diagrams illustrating the main components and the pin definitions.

Image: Detailed diagram of the EoRa-S3-900TB board highlighting key components and their functions, including the LoRa module, ESP32-S3 chip, and various interfaces.
5.1. Component Introduction
| ŽÁDNÝ | Hlavní hardware | Úvod do komponenty |
|---|---|---|
| 1 | E22-400MM22S or E22-900MM22S | Ultra-small size independently developed by Chengdu Ebyte Electronics Co., Ltd. Based on the new generation of LoRa RF chip SX1262. E22-400MM22S and E22-900MM22S are produced by American Semtech and are suitable for 433MHz, 470MHz, 868MHz and 915MHz patch-type LoRa wireless modules. |
| 2 | ESP32-S3 chip | ESP32-S3 is a low-power MCU system-on-chip (SoC) that supports 2.4GHz Wi-Fi and Bluetooth LE wireless communication. |
| 3 | 3D omnidirectional antenna (Wi-Fi antenna) | Maximum gain 4.9dBi, 2.4G Wi-Fi omnidirectional antenna |
| 4 | IPEX seat (Wi-Fi antenna) | IPEX first generation socket, 2.4G Wi-Fi antenna |
| 5 | IPEX seat (LoRa antenna) | IPEX first generation seat, LoRa antenna |
| 6 | SMA radio frequency interface (LoRa antenna) | Full length 14.5mm SMA head, LoRa antenna |
| 7 | Resetovací klíč | Tlačítko reset |
| 8 | přepínač | For completely disconnecting battery power |
| 9 | GPIO external interface | GPIO from ESP32 |
| 10 | GPIO external interface | UART serial port TXD |
| 11 | Rozhraní pro externí baterii | SH 1.25mm, 2pin battery interface |
| 12 | Jednobarevná LED | Addressable RGB LED, driven by GPIO8 |
| 13 | Dvoubarevná LED | Charging indicator light, red when charging, green when fully charged |
| 14 | OLED obrazovka | 0.96palcový OLED displej |
| 15 | Zaváděcí klíč | Download button. Press and hold the Boot key and press the Reset key to enter the "firmware download" mode and download the firmware through the serial port. |
| 16 | USB download port | USB interface can be used as the power supply for the development board or the communication interface between PC and ESP32-S3 chip |
| 17 | Slot pro TF kartu | Short body TF card slot |
| 18 | Kolík | All available GPIO pins (except the SPI bus of the flash) have been led to the pin header of the development board. Please see pin headers for more information. |
5.2. Definice pinů

Image: Diagram illustrating the pin layout and dimensions of the EoRa-S3-900TB board, crucial for connecting external components.
| ŽÁDNÝ | Název PIN | Typ kolíku | Použití pinu |
|---|---|---|---|
| 1 | VCC | Napájení | Power pin, can be used as 5V power output after normal power supply |
| 2 | GND | Napájení | Síla GND |
| 3 | 3.3 VA | Napájení | The power pin can be used as a 3.3V power output after normal power supply. It is not allowed to connect to 3.3V or other external power. |
| 4 | GND | Napájení | Síla GND |
| 5 | GPIO42 | Vstup výstup | - |
| 6 | GPIO46 | Vstup výstup | - |
| 7 | GPIO41 | Vstup výstup | - |
| 8 | GPIO40 | Vstup výstup | - |
| 9 | GPIO39 | Vstup výstup | - |
| 10 | U0RXD | Vstup | UART serial port RXD |
| 11 | U0TXD | Výstup | UART serial port TXD |
| 12 | GPIO38 | Vstup výstup | - |
| 13 | GPIO16 | Vstup výstup | - |
| 14 | GPIO15 | Vstup výstup | - |
| 15 | RST | Vstup výstup | Connect to ESP32-S3 reset pin |
| 16 | GPIO08 | Vstup výstup | Connect to the reset pin of the LoRa module |
| 17 | GPIO12 | Vstup výstup | - |
| 18 | GPIO48 | Vstup výstup | - |
| 19 | GPIO47 | Vstup výstup | - |
| 20 | GPIO35 | Vstup výstup | Connect to DIO1 of LoRa module |
| 21 | GPIO34 | Vstup výstup | BUSY connected to LoRa module |
| 22 | GPIO33 | Vstup výstup | - |
| 23 | GPIO36 | Vstup výstup | BOOT button connected to the base panel |
| 24 | GPIO37 | Vstup výstup | LED connected to base plate |
| 25 | GPIO38 | Vstup výstup | - |
| 26 | GPIO37 | Vstup výstup | - |
6. Začínáme
6.1. Napájení desky
The EoRa-S3-900TB can be powered via its Type-C USB port. Connect the board to a computer or a 5V USB power adapter using a standard Type-C cable. The board also supports Li-ion battery power, with an integrated charging circuit. Ensure the battery is connected to the external battery interface (SH 1.25mm, 2pin) if using battery power.
6.2. Stažení firmwaru
To upload new firmware or programs to the ESP32-S3 chip:
- Connect the board to your computer via the Type-C USB download port.
- Stiskněte a podržte Zaváděcí klíč (labeled 15 in the component introduction diagram).
- While holding the Boot key, briefly press the Resetovací klíč (labeled 7).
- Release the Boot key. The board should now be in firmware download mode, ready to receive firmware via the serial port.

Image: The EoRa-S3-900TB board featuring its integrated 0.96-inch OLED display, which can be used for status indicators or data output.
7. Provozní režimy
7.1. Wi-Fi Operating Modes
The ESP32-S3 supports various Wi-Fi operating modes:
- Infrastructure BSS Station mode (STA mode): The module acts as a client and connects to an existing Wi-Fi access point or router. In this mode, the module does not provide connections to other devices.
- SoftAP mode (AP mode): The module functions as a wireless access point, allowing other Wi-Fi devices to connect to it. It can establish TCP/IP-based server, client, and UDP connections, supporting up to 6 stations and up to 7 TCP Socket transmissions.
- Station + SoftAP mode: The module operates simultaneously as both a client (STA) and an access point (AP).

Image: Visual representation of the Wi-Fi operating modes (AP and STA) supported by the EoRa-S3-900TB board, illustrating how it can function as an access point or connect to an existing network.
7.2. Bluetooth LE Data Rates
The Bluetooth LE functionality supports multiple data rates, providing flexibility for various applications:
- 125 kbps
- 500 kbps
- 1 Mbps
- 2 Mbps

Image: Diagram illustrating the adjustable multi-level data rates for Bluetooth Low Energy (BLE) supported by the board, ranging from 125 Kbps to 2 Mbps.
8. Aplikační scénáře
The EoRa-S3-900TB board is suitable for a wide array of applications due to its versatile connectivity and processing capabilities:
- Smart home and industrial automation
- Healthcare devices
- Smart agriculture systems
- Service robotics
- General Purpose Low Power IoT Sensor Hubs
- General Purpose Low Power IoT Data Loggers
- Audio devices and camera video streaming
- USB devices and consumer electronics
- Speech recognition and image recognition systems
- Wi-Fi + Bluetooth network cards
- Touch and proximity sensing applications

Obrázek: Přamples of diverse application scenarios for the EoRa-S3-900TB, including smart home, medical equipment, audio equipment, smart agriculture, service robots, and electronic products.
9. Řešení problémů
If you encounter issues with your EoRa-S3-900TB board, consider the following common troubleshooting steps:
- Bez napájení: Ensure the Type-C cable is securely connected and the power source (USB port or adapter) is functional. If using a battery, check its charge level and connection.
- Chyba při nahrávání firmwaru: Verify that the board is in download mode (Boot key pressed during reset). Check your serial port settings and driver installation on your computer.
- Problémy s připojením k Wi-Fi/Bluetooth: Ensure antennas are properly connected. Check your code for correct Wi-Fi credentials or Bluetooth pairing procedures. Verify that the module is operating in the correct mode (AP, STA).
- OLED displej nefunguje: Check connections to the OLED display. Ensure your code is correctly initializing and sending data to the display.
- SD karta nebyla detekována: Ensure the SD card is inserted correctly into the TF card slot. Check your code for proper SD card initialization and file systémové operace.
10. Údržba
To ensure the longevity and optimal performance of your EoRa-S3-900TB board:
- Udržujte v čistotě: Regularly clean the board with a soft, dry brush or compressed air to remove dust and debris. Avoid using liquids or harsh chemicals.
- Zacházejte opatrně: Avoid dropping the board or subjecting it to physical shocks. Handle by the edges to prevent damage to components.
- Správné skladování: Store the board in a dry, cool environment, away from direct sunlight and extreme temperatures. Use anti-static bags if storing for extended periods.
- Vypnutí, když se nepoužívá: Disconnect power when the board is not in use, especially if using battery power, to prevent unnecessary discharge.
11. Podpora a záruka
For technical support, documentation, or further inquiries regarding the EoRa-S3-900TB test board, please contact the manufacturer:
Výrobce: Chengdu Ebyte Electronic Technology Co., Ltd.
Webmísto: http://www.cdebyte.com/
For EU customers, the authorized representative is:
REP EU: evalmaster Consulting GmbH
Bethaniestr. 30
60325 Frankfurt nad Mohanem
Německo
Please refer to the product packaging or purchase documentation for specific warranty terms and conditions.