Amazon Sidewalk - Sub-GHz SX1262 Radio Component#

This driver provides Sidewalk support for the Semtech SX1262 radio, enabling FSK and CSS (LoRa) modulations. It wraps the Semtech-provided SX1262 radio driver with additional logic for Sidewalk-specific framing, timing, and profile management. It does not include or support LoRaWAN stack features and is intended exclusively for Sidewalk endpoint implementations.

⚠ WARNING ⚠: Sub-GHz communication operates in the 915MHz band, which is open in the US but may be restricted in other regions. Ensure compliance with local regulations.

⚠ WARNING ⚠: Amazon Sidewalk is currently not supported in Europe.

Component Overview#

The Sidewalk Sub-GHz SX1262 component provides:

  • Radio Driver: Complete SX1262 radio driver implementation with HAL (Hardware Abstraction Layer)

  • Modulation Support: FSK and CSS modulation schemes for Amazon Sidewalk

  • Regional Compliance: Support for US915 frequency band

  • Power Management: Configurable transmit power with regional limits

  • SPI Interface: Standard SPI communication with the SX1262 chip

  • GPIO Control: Reset, DIO, and busy signal management

Hardware Requirements#

Supported Hardware Configurations#

KG100S Module#

  • Built-in SX1262: The KG100S module has the SX1262 radio chip integrated

  • No External Board Required: Direct connection to the module's built-in radio

  • Enhanced Features: RX boost enabled for improved sensitivity

Other Development Boards#

  • External SX1262 Board Required: Must connect an SX1262 extension board

  • SPI Interface: Standard SPI communication with the external radio

  • GPIO Connections: Using WSTK with development board and SX1262 extension board, the correct pins are configured by default

Required Connections#

GPIO Connections#

Signal

GPIO Pin

Description

SL_PIN_NRESET

Configurable

Radio reset signal (active low)

SL_PIN_DIO

Configurable

Radio interrupt signal

SL_PIN_BUSY

Configurable

Radio busy signal

SL_PIN_NSS

Configurable

SPI chip select

Features#

Radio Capabilities#

  • Frequency Range: 902-928 MHz (US915 band)

  • Transmit Power: -9 to +22 dBm (hardware limited)

  • Regional Power Limits:

    • US915: Maximum 20 dBm

  • Modulation Schemes:

    • FSK: Frequency-Shift Keying for reliable data transmission

    • CSS: Chirp Spread Spectrum for long-range communication

  • Data Rates: Configurable based on modulation and regional requirements

Regional Support#

The component supports the US915 regulatory region:

Region

Frequency Band

Max TX Power

Antenna Gain

US915

902-928 MHz

20 dBm

2.15 dBi

Ⓘ INFO Ⓘ: Amazon Sidewalk is currently only supported in the United States.

Usage#

Integration Steps#

  1. Add Component: Include Sidewalk Sub-GHz SX1262 in your project

  2. Configure SPI: Set up SPI peripheral in your project configuration

  3. Connect GPIO: Wire the required GPIO signals to your SX1262 radio

  4. Configure Power: Set transmit power based on regional limits

  5. Test Communication: Verify SPI communication with the radio

Ⓘ INFO Ⓘ: Steps 2 and 3 are performed automatically when using a mainboard with a development board and an SX1262 extension board.

GPIO Configuration#

The GPIOs required for the SX1262 radio (such as RESET, DIO, and BUSY) can be configured in your project at config/app_gpio_config.h. This file allows you to map the necessary GPIO pins to your hardware setup as needed.

Transmit Power Configuration#

Regional Power Limits#

The component automatically enforces regional power limits:

  • US915: Maximum 20 dBm transmit power

  • Power is automatically limited to regional maximum

Conflicts and Compatibility#

Component Conflicts#

This component conflicts with other Sub-GHz implementations:

  • Sidewalk Sub-GHz LR1110 (Semtech LR1110)

  • Sidewalk Sub-GHz efr32xgxx (EFR32 built-in radio for other families)

Device Compatibility#

  • Supported:

    • KG100S module (built-in SX1262)

    • External SX1262 hardware with SPI interface

    • EFR32xG28 with external SX1262 board

  • Not Supported:

    • Built-in radio devices (EFR32xG23, EFR32xG25, except EFR32xG28 with external board)

    • Other external radio chips

  • Requires: Hardware board with external radio support

Additional Resources#

To use this component through Sub-GHz Interface, see the Sub-GHz Interface in the Sidewalk SDK API documentation.

Report Bugs & Get Support#

For technical support, bug reports, or questions about this component, please visit the Silicon Labs Community.

License#

This component is licensed under:

  • Zlib License: Silicon Labs software license

  • Amazon Sidewalk License: Additional terms for Amazon Sidewalk functionality

See the component source files for complete license information.