Sentera internet gateway
The gateway can be connected to the Sentera devices using either an Ethernet cable or a Wi-Fi network.
1. How WIZnet products are used
Internal board photos confirm the use of a CETUS JB1821C0D Ethernet module, which integrates the WIZnet W5500 chip.
The W5500 handles the full TCP/IP stack in hardware, enabling efficient, reliable Ethernet communication with minimal load on the main MCU.
This allows the DIG-M-2 to maintain a stable and secure cloud connection while ensuring precise real-time Modbus RTU communication over RS485.
2. Technologies, techniques, and unique implementation
Modbus RTU over RS485: An industrial standard communication protocol; the gateway collects data from multiple slave devices
Automatic cloud sync: No need for custom backend servers—auto-registers to the SenteraWeb platform
RJ45 for both power & data: Simplified wiring through a unified port
Dual network modes: Supports both Ethernet and Wi-Fi for flexible deployment
Built-in web UI: Offers scheduling, status monitoring, firmware updates, and configuration directly via browser without external tools
3. Overall project flow
RS485 connection
Legacy HVAC devices stay connected via RS485
DIG-M-2 acts as a Modbus RTU master or client
Internet connection
Device connects via Ethernet or Wi-Fi
Cloud registration is automatic through SenteraWeb
Data exchange
Modbus RTU data is read and transmitted to the cloud
Remote changes from the cloud are pushed back as Modbus commands
Remote UI access
SenteraWeb provides full control: monitor temperatures, change fan speeds, set schedules, receive notifications
Maintenance & scalability
Firmware updates can be pushed remotely
Multiple devices are manageable through a single cloud dashboard
4. Technical synergy with WIZnet
WIZnet Ethernet solutions complement the DIG-M-2 design by:
Ensuring robust connectivity with hardware TCP/IP stack
Minimizing MCU load, enabling precise Modbus timing and command handling
Simplifying DNS and cloud communication with built-in protocol support
Enabling secure and scalable deployment for multiple gateways
In this context, WIZnet hardware offers a high-reliability, low-maintenance network layer that perfectly aligns with cloud-connected Modbus RTU applications.
5. Application ideas and potential extensions
Retrofit existing Modbus RTU systems for cloud-based operation without changing hardware
Smart building automation: integrate HVAC, ventilation, and lighting into one remote dashboard
OEM-ready gateway platform: manufacturers can bundle it with their control devices
Energy analytics platform: collect usage data to optimize performance and reduce costs
Remote service & diagnostics: minimize technician dispatch by pre-analyzing issues via the cloud
Alarm and event management systems: use real-time alerts for proactive maintenance