HardwareA0 IoT Gateway
Swiss knife for wireless IoT - Modular multi-protocol IoT gateway
A0 IoT Gateway
The A0 IoT Gateway is a robust and modular IoT Gateway for smart metering applications. Built around the ESP32-C6 microcontroller with a RISC-V core, it runs Zephyr RTOS and supports Wireless M-Bus (wMBus) utility meters via a plug-in module, transmitting collected data securely to Magistrala.
A0 = A0 Base Board + ESP32-C6 Module + Expansion Modules — Zephyr RTOS
Looking for a Linux-based gateway? See the A1 Gateway, which combines the A0 Board with BeagleV-Fire.
Overview
A0 collects data from multiple wireless protocols and transmits it securely to the cloud. It integrates with Magistrala, a modern, scalable, open-source IoT platform.
Hardware Architecture
The A0 gateway is built on the A0 base board — a low-power, battery-capable carrier with external power supply support — with an ESP32-C6 module on top. Additional radio and cellular connectivity is added via two plug-in expansion slots, BUS1 and BUS2, where any supported module can be fitted.
ESP32-C6 Module
The ESP32-C6 is Espressif's first Wi-Fi 6 SoC, integrating 2.4 GHz Wi-Fi 6 (802.11ax), Bluetooth 5 (LE), and IEEE 802.15.4 (Thread/Zigbee) in a single low-power chip. Key specifications:
| Spec | Details |
|---|---|
| CPU | High-performance 32-bit RISC-V core up to 160 MHz + low-power (LP) 32-bit RISC-V core up to 20 MHz |
| Memory | 320 KB ROM, 512 KB SRAM, external flash |
| Wireless | Wi-Fi 6 (802.11ax, 20 MHz) + 802.11 b/g/n (20/40 MHz); OFDMA up/downlink, downlink MU-MIMO, Target Wake Time (TWT); Bluetooth 5 LE (coded PHY long-range, 2 Mbps high-throughput); IEEE 802.15.4 |
| Security | RSA-3072 secure boot, AES-128/256-XTS flash encryption, digital signature & HMAC peripherals, hardware crypto accelerators, Trusted Execution Environment (TEE) |
| Software | ESP-IDF, Zephyr RTOS, ESP-Hosted / ESP-AT, ESP RainMaker |
Wi-Fi 6 features (OFDMA, MU-MIMO, TWT) deliver low latency and multi-year battery life in congested RF environments, while the combined Wi-Fi + BLE + 802.15.4 radios enable Matter, Thread Border Router, and Zigbee scenarios.
Core Components
| Component | Description |
|---|---|
| ESP32-C6 module | Main microcontroller (RISC-V, Wi-Fi 6, BLE, 802.15.4), mounted on the A0 base board |
| A0 base board | USB-C, external supply, and battery with charging (MCP73831 charger + XL1509-5.0 buck → AMS1117-3.3 LDO pair — see Base Board) |
| BUS1 / BUS2 | Two expansion slots for plug-in connectivity modules |
| SIM7080G | NB-IoT/LTE-M + GNSS module (optional) |
| WMBUS | Wireless M-Bus module (optional) |
| E07-400M10S | Sub-GHz 400 MHz module (optional) |
| USB-C & Terminals | For power and debug |
The board exposes IPEX antenna connectors per radio (Wi-Fi, GNSS/NB-IoT, wM-Bus — depending on fitted modules).
Connectivity Options
- Receive Data: WiFi, BLE, 802.15.4, Wireless M-Bus, sub-GHz, I2C, SPI, UART
- Transmit Data: NB-IoT, LTE-M, WiFi
Power Management
The A0 board can be powered in 3 ways:
- USB-C: For development and testing
- External supply: Via the supply input terminal (VIN)
- Battery: Via the battery JST connector, with charging via the on-board MCP73831 charger
On board, the XL1509-5.0 buck generates the 5 V rail (FB_5V) and a pair of AMS1117-3.3 LDOs regulate down to +3V3 — see the A0 Base Board for the full chain.
Wireless Communication
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WiFi/BLE: The ESP32-C6 provides 2.4GHz Wi-Fi and BLE. An IPEX connector on the ESP32-C6 accepts a 2.4GHz antenna of your choice.
-
Wireless M-Bus: The plug-in WMBUS module (S2-LP-based) enables wireless M-Bus communication with wMBus meters at 868 MHz. An IPEX connector accepts a 868 MHz antenna.
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NB-IoT / LTE-M: The SIM7080G module provides NB-IoT/LTE-M connectivity. Two IPEX connectors handle RF (wireless) and GNSS (GPS) antennas. The SIM7080G is controlled via AT commands from the ESP32.
Firmware and Flashing
The A0 board uses the ESP32-C6 as its main microcontroller and can be programmed using any framework of your choice. Firmware is flashed through the USB-C connector.
Debug is possible via the USB-C connector or the JTAG pins labelled on the board, enabling both on-site and off-site debugging.
Software Stack
Zephyr RTOS
A0 runs on Zephyr RTOS, providing:
- Secure and modular firmware stack
- Built-in protocol support (MQTT, CoAP, WebSockets, HTTP)
- Open-source foundation for transparency and maintainability
- Community-driven innovation
Magistrala Integration
Native integration with Magistrala IoT platform:
- Seamless data ingestion and device management
- Secure cloud connectivity
- Open-source and patent-free
- Scalable architecture
Software Features
The gateway firmware:
- Collects meter data periodically from Wireless M-Bus meters
- Transmits structured data securely to Magistrala via MQTT
- Manages reconnections and retry logic for unreliable NB-IoT networks
- Logs diagnostics and status via UART or remote logging service
Supported communication protocols:
| Protocol | Security | Description |
|---|---|---|
| MQTT | No | Lightweight messaging protocol for IoT data exchange |
| MQTTS | Yes | Secure MQTT communication over TLS (mTLS supported) |
| CoAP | No | REST-based protocol optimized for constrained devices |
| CoAP DTLS | Yes | Secure CoAP communication using DTLS encryption |
| HTTP | No | Standard web communication protocol |
| HTTPS | Yes | Secure version of HTTP over TLS |
| WebSockets | Yes | Full-duplex communication protocol over TCP |
Expansion Options
Expansion Modules (BUS1 / BUS2)
The A0 base board provides two expansion slots (BUS1 and BUS2) supporting the in-house modules:
- SIM7080G — NB-IoT/LTE-M cellular uplink + GNSS
- WMBUS — Wireless M-Bus metering radio
- E07-400M10S — Sub-GHz (400 MHz, 10 dBm) radio
Because the expansion slots use the MikroE Click footprint, the MikroE Click boards™ ecosystem is also supported — see Modules.