IIoT and Gateway Nodes

IIoT & Gateway Nodes

Article Type: Node Reference Audience: Developers, App Admins, IIoT Engineers Module: Data Flows / Edge Gateway Applies to Versions: Platform 3.0+ Prerequisites: Understanding of Data Flow concepts, Edge Gateway installed

1. Overview

What are IIoT Nodes?

The Fuuz platform goes beyond other solutions in providing you with an unparalleled ability to integrate with and interact with devices and other assets outside of software products — things like industrial controllers, weigh scales, label printers, RFID portals and much more.

IIoT (Industrial Internet of Things) nodes enable Data Flows to communicate with physical devices through the Edge Gateway. The gateway acts as a bridge between the cloud platform and on-premise industrial equipment.

Key Architecture Concepts:

• Gateway — On-premise software that connects to physical devices and communicates with Fuuz
• Device Driver Type — A category of drivers sharing common functionality (e.g., PLC, Printer)
• Device Driver — A specific driver implementation for a device protocol (e.g., Ethernet/IP PLC, TCP Printer)
• Connection — A configured instance connecting to a specific physical device
• Subscription — A configuration for receiving events from a device

IIoT Node Types

Node	Purpose	Use Case
Print File Node	Print a Fuuz-stored file through the gateway	Print labels, reports stored in platform
Print Data Node	Print dynamically generated content (Base64)	Print rendered PDFs, dynamic labels
Execute Device Function Node	Execute any device function generically	Read/write PLC tags, query device status
Subscription Node	Subscribe to device events (Source node)	React to PLC tag changes, file events

2. Gateway Architecture

The Gateway is an on-premise application that bridges Fuuz with physical devices and other resources inside the DMZ. Understanding its architecture is essential for working with IIoT nodes.

Configuration Hierarchy

Level	Description
Gateway	The installed gateway instance (hostname, IP, status)
Device Driver Type	Category of drivers (PLC, Printer, Modbus, etc.)
Device Driver	Specific protocol implementation (Ethernet/IP PLC, TCP Printer)
Connection	Configured instance for a specific physical device, folder, or other resource
Subscription	Event configuration for receiving data from a device or other publisher

Available Device Driver Types

Driver Type	Available Drivers	Use Cases
PLC	Ethernet/IP PLC (Allen-Bradley)	Read/write tags, browse tags, machine integration
PCCC PLC	PCCC PLC Driver	Legacy Allen-Bradley PLCs using PCCC protocol
Printer	Native Printer, TCP Printer	Label printing, document printing, Windows only
Modbus	Modbus TCP	Industrial automation, sensors, actuators
OPC-UA	OPCUA Client	Industrial interoperability, unified automation
MQTT	MQTT Client, MQTT Broker	IoT messaging, telemetry data, SparkplugB
File	File Driver	Folder monitoring, file operations
Server	HTTP Server, TCP Server, MQTT Broker	Receive inbound connections
HTTP	HTTP Client	REST API calls from gateway
TCP	TCP Socket Driver	Raw TCP communication
SQL	Oracle DB, MySQL	Direct database access from gateway

3. Print File Node

A specialized node used to call the "Print File" device function. This can be used to print a Fuuz file (stored in the platform) through the Edge Gateway.

Configuration Parameters

Parameter	Description
Printer	The printer device to send the file to. This is a transformable field.
File	A file stored in Fuuz. This is a transformable field.
Function Timeout (optional)	Time to wait before error. Default: 60 seconds.
Request ID Transform (optional)	Unique ID to track the request. Default: auto-generated CUID.

Tip: Use Print File when you have a static file already stored in Fuuz that needs to be printed. For dynamically generated content, use Print Data instead.

4. Print Data Node

A specialized node used to call the "Print Data File" device function. This can be used to print PDF files or other dynamically generated content through the Edge Gateway.

Configuration Parameters

Parameter	Description
Printer	The printer device to send the file to. This is a transformable field.
Document Content Transform	Transform that returns a Base64-encoded string representing the file to be printed.
File Name (optional)	Name for the temporary file written to gateway disk. Default: random name.
Function Timeout (optional)	Time to wait before error. Default: 60 seconds.
Request ID Transform (optional)	Unique ID to track the request. Default: auto-generated CUID.

Common Pattern: Combine with Render Document node to generate a PDF, then use Print Data to send the Base64-encoded PDF to a printer.

5. Execute Device Function Node

This node is a generic node used to call device functions. Once a device function is selected, more fields will be added to provide inputs for the parameters specific to that device function. The node will attempt to provide the simplest form input if able to enumerate a specific type; otherwise a JSONata transform input will be provided.

Configuration Parameters

Parameter	Description
Device	Select the device to execute the function against
Function	The device function to execute (varies by device type)
Request Parameters	Function-specific parameters (dynamically added based on function)
Function Timeout (optional)	Time to wait before error. Default varies by function.

Common Device Functions by Type

Driver Type	Function	Description
PLC	Browse Tags	Browse available tags on the PLC device
	Read Tag	Read a single tag value from the PLC
	Write Tag	Write a value to a single PLC tag
	Write Tags	Write values to multiple PLC tags
Printer	Print	Send a document (PDF) to the printer
	Get Jobs	Query the job queue of the printer
	Status	Check the printer status
Modbus	Read Registers	Read holding registers from Modbus device
	Write Registers	Write to holding registers on Modbus device
File	List	List files in a directory
	Read	Read file contents
	Status	Check the status of the root folder
TCP	Status	Check if the TCP socket is connected

6. Device Subscription Node

A node used to subscribe to devices setup in Fuuz through the gateway. Any dropdowns left blank will act as a wildcard, allowing you to subscribe to multiple subscriptions with one node. This is a Source node that triggers flows when device events occur.

Configuration Parameters

Parameter	Description
Device Driver Type	The base driver type (e.g., Printer, PLC). Blank = wildcard.
Device Driver	The specific driver (e.g., Native Printer, TCP Printer). Blank = wildcard.
Device	The specific device to listen for events on. Blank = wildcard.
Edge Gateway	The gateway to receive events from (if multiple gateways). Blank = wildcard.
Device Subscription Type	The type of subscription event to listen for.
Device Subscription	The specific subscription configuration.

Device Subscription Types

Subscription Type	Description
File System Change	Watch for file/folder changes (ADD, CHANGE, DELETE, ALL). Supports depth and polling options.
HTTP POST Endpoint	Receive HTTP POST requests at a configured endpoint path.
Tag Values	Subscribe to PLC tag value changes. Supports Store and Forward.
PCCC Tag Values	Subscribe to PCCC PLC tag value changes.
OPC-UA Node Values	Subscribe to OPC-UA node value changes.

Important: Device subscriptions must be deployed before the flow will receive events. The subscription stream is not started until the flow is deployed.

7. PLC Tag Configuration

When working with PLCs, understanding tag configuration is essential for reading and writing values correctly.

Supported PLC Data Types

Type	Description
BOOL	Boolean (true/false)
INT	16-bit signed integer
SINT	8-bit signed integer
DINT	32-bit signed integer
LINT	64-bit signed integer
UINT	16-bit unsigned integer
REAL	32-bit floating point
STRING	ASCII string

Tag Configuration Parameters

Parameter	Description
Tag	The name or address of the tag on the PLC
Scope (optional)	The program scope. If not provided, reads from Global scope.
Type	The data type of the tag (required for writes)
Value	The value to write (for write operations)

Store and Forward

Tag subscriptions support Store and Forward mode for reliable data delivery:

• Enabled: Tag values are stored on disk until they can be successfully pushed to Fuuz
• Disabled: Tag values attempt to be sent immediately (may be lost if connection fails)
• Continuous Values: When enabled with Store and Forward, all tag value updates are pushed. Otherwise, only the latest value is pushed.

8. Printer Configuration

Native Printer Driver (Only for Windows Installations)

Uses the system print spooler to send documents and commands. The printer must be installed on the gateway machine.

Parameter	Description
Printer Name	The name of the installed printer, including printer server prefix if applicable

TCP Printer Driver

Uses a direct TCP network connection to send documents and commands. Common for label printers like Zebra. Functions with non-Windows deployments, like Docker / Portainer installations.

Parameter	Description
Host	Hostname or IP address of the printer
Port	TCP port (default: 9100)
Status Command (optional)	Printer command to query status. If not provided, a connection test is performed.
Status Response Parser (optional)	JSONata transform to parse status response. Returns {ok, message, info}.

9. Gateway Functions

The Edge Gateway itself has administrative functions that can be called from Data Flows.

Function	Description
Get Gateway Status	Returns hostname, IP, MAC address, application version, status, and uptime
Apply Gateway Updates	Install available gateway and/or driver updates
Get Driver Devices	List devices connected to the gateway for a specific driver
List Log Files	List available log files on the gateway

10. Troubleshooting

Symptom	Likely Cause	Resolution
Device not showing in dropdown	Gateway offline or device not configured	Check gateway status; verify device configuration
Function timeout errors	Device unreachable or slow response	Increase function timeout; verify network connectivity
PLC tag read returns null	Invalid tag name or scope	Use Browse Tags to verify tag exists; check scope
Print job not printing	Printer offline or queue blocked	Check printer status function; clear print queue
Subscription events not triggering	Flow not deployed	Deploy the flow; verify subscription configuration
File System Change not detecting	Network folder requires polling	Enable Polling option for network folders

11. Related Resources

• Source-and-Trigger-Nodes — Device Subscription node details
• Fuuz-Platform-Nodes — Render Document for PDF generation
• Edge-Gateway-Application — Gateway setup and management
• Edge-Connections-Complete-Industrial-Integration-Reference — Setting up drivers, devices, and connections
• Gateway-Deployment-and-Architecture
• Data-Flow-Nodes-Reference
• Platform website: fuuz.com

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Source: support.fuuz.com