2. Hardware Overview

SMHUB is a Linux-based modular hub designed to unify connectivity, automation, and control across multiple smart home and IoT standards. Its hardware architecture combines high-performance networking, multiple radios, built-in peripherals, and modular power options.

2.1 Core System

• Processor: 2 separate cores: C906@1GHz (for Linux) + C906@700MHz (for RTOS).
  C906 is an ultra-high-efficiency processor compatible with the RV64IMA[F]C[V] instruction set. It is one of the industry's first mass-produced processors supporting the RISC-V vector extension.
  

• NPU (Neural Processing Unit): 0.5 TOPS@INT8.

• Memory: 512 MB RAM.

• Storage: Onboard eMMC storage plus microSD slot for expansion.

• Operating System: Embedded Linux with Node.js runtime, supporting smart applications such as Zigbee2MQTT, Matterbridge, Node-RED, and custom Node.js/Python services.

2.2 Networking

• Ethernet: Integrated RJ-45 port for wired backbone connectivity.

• Wi-Fi:

  • Dual-band 2.4 GHz and 5 GHz support.

  • Can operate in Access Point mode or Client mode.

  • CLI setup available, with web UI configuration in development.

• Bluetooth:

  • Bluetooth 5.0 compliant.

  • Supports Bluetooth Low Energy (BLE) for pairing, sensors, and beacons.

  • Available for integrations and custom applications.

2.3 Radios

• Zigbee (CC26xx) → dedicated radio for Zigbee networks, fully compatible with Zigbee2MQTT.

• Thread (EFR32MG series) → native support for Thread and OpenThread Border Router (OTBR).

• EFR32ZG23 Expansion Module → provides Sub-GHz communications including Z-Wave, integrated via UART3 with dedicated reset, flash, and LED lines.

2.4 Expansion Modules

• UPS Module (SM-HUB UPS)

  • Powered by 18650 Li-ion battery cells.

  • Charging via TP5100.

  • Step-up/step-down converters deliver 5 V, 3.3 V, and 1.8 V rails.

  • INA226 sensor monitors voltage and current for telemetry.

  • Solar/DC charging input supported.

• PoE Module (SM-HUB PoE)

  • 802.3af compliant (Power over Ethernet).

  • Converts Ethernet-supplied power to regulated 5 V.

  • Surge and ESD protection integrated.

  • “Power-check” signals exposed for system monitoring.

• 4G/LTE Module (SM-HUB 4G)

  • Based on SIM7672G modem with GNSS (GPS/GLONASS).

  • NanoSIM slot with SIM detect.

  • Interfaces: main UART, USB, debug UART.

  • LTE and GNSS antenna connectors.

  • Power and network LED indicators.

2.5 Built-in Peripherals

• LEDs:

  • 12 × WS2812B addressable RGB LEDs – configurable for system visualization, animations, or Ambilight effects.

  • 4 × service LEDs – indicating power, network, and radio activity.

• Buttons:

  • Reset button.

  • Pairing/Function button.

  • User-configurable button.

• Audio Output:

  • 3.5 mm audio jack.

  • Supports system notifications, alerts, or media playback.

• Buzzer:

  • Integrated piezoelectric buzzer.

  • Usable for system alerts, notifications, or user automation rules.

• IR Modules:

  • IR transmitter for controlling TVs, AC units, and other IR devices.

  • IR receiver for capturing signals from existing remotes.

2.6 Power Architecture

• Primary Power: USB-C PD input.

• Optional Power Sources:

  • PoE (via PoE module).

  • UPS battery module.

  • Solar/DC input (through UPS module).

• Smart USB Power Switching: Automatic host/device detection on USB-C CC lines with integrated FET switching. Prevents reverse powering and ensures safe operation whether SMHUB is supplying power to peripherals or being powered itself.

2.7 Expansion & DIY Interfaces

For developers and hardware enthusiasts, SMHUB exposes additional interfaces:

• GPIO headers with UART, SPI, and I²C.

• DIY pinouts for custom modules, sensors, or experimental expansions.