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Digital I/O

The digital inputs/outputs can be used to trigger sending of SMS messages based on input state, or to activate external devices when SMS messages are received.

Function Details

SMSEagle NXS-line devices are equipped with digital inputs (DI) and digital outputs (DO). The digital inputs can be used to receive signals from outside sensors or devices and automatically trigger sending of SMS message based on input state. On the other hand the digital outputs may be used to activate external devices connected to the outputs when certain SMS messages are received by SMSEagle.

Configuration

The “Digital I/O” feature allows you to define rules that control the behavior of digital inputs/outputs on SMSEagle device. User may define several processing rules for both inputs and outputs.

Digital inputs

For each processing  rule for digital input user can define:

  • The rule name
  • Port number
  • State of input signal that will trigger sending of SMS message (field “When input signal”)
  • SMS text (field “Send SMS message”)
  • The recipient’s name from phonebook
  • Alert timeout

Digital Outputs

For each processing  rule for digital output user can define:

  • The rule name
  • Port number
  • On what condition digital output should be set (all incoming messages, when incoming SMS comes from specified contact in phonebook and/or when incoming SMS text contains given value)
  • State of output signal that will be triggered by incoming SMS message
  • Output signal duration in seconds (0 = without time limit)
  • Output signal delay before signal is set
  • Define outgoing SMS that will be sent after output signal is triggered

Voice Calls

SMS message that was triggered by a digital input/output rule can be optionally followed by a wake-up call or text-to-speech call. This can be enabled in the rule definition. The feature requires a device with active Voice-Call add-on.

Reliable integration with digital systems

Integrating external devices with your SMS-based communication system often means complex programming or additional hardware. SMSEagle’s digital inputs/outputs feature simplifies much of this, but it’s important to understand how it works.

Digital I/O functionality centers around detecting state changes—specifically, whether a circuit is open or closed (logic 0 or 1). That means SMSEagle can detect when a device turns on or off, and then act on that change. What happens next depends heavily on the external hardware. For example, if a motion sensor turns on a lamp when movement is detected, and that lamp triggers a change in input state, SMSEagle can respond with a message. But the action must cause a detectable change in the digital signal.

Rather than being a general-purpose sensor integration, this method focuses on reliably translating real-world signal changes into SMS messages. When devices are designed to signal via a digital ON/OFF change, SMSEagle helps you make the most of that capability.

Designed for practical, real-time action

SMSEagle reacts instantly to changes in digital input state—whether a device switches on or off, or a circuit moves from 0 to 1 (or vice versa). You define the rules for how the system responds, ensuring clear and immediate reactions to physical changes in your environment.

This capability is essential in a wide range of applications. In factories, entire machines or production lines can be monitored for state changes. In server rooms, it’s critical to know when a fault occurs and when systems come back online. Early warnings or alarm resets can be tied directly to digital signals in building automation and safety systems.

Digital outputs are just as flexible. You can control connected devices remotely via SMS—activating relays, opening gates, or resetting systems—based on predefined commands and timing options.

The strength of this feature lies in its simplicity: reliable detection and control through binary digital signals, with instant SMS communication to match.

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SMS Gateway?

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in the User's Manual

Tailored rules without the learning curve

Setting up your I/O rules doesn’t require coding, but a proper understanding of your hardware’s behavior. You define rules based on changes in signal state and set message contents, recipients, and output behavior.

Some logic can be built directly into the external device, and SMSEagle will respond to any resulting state change. Whether it’s a machine powering on, an alarm deactivating, or a system reset being triggered, once that change is visible on the input, the platform can send an SMS immediately. This makes it highly effective for monitoring equipment status, automation events, and operational transitions across various industries.

The focus is on simplicity and control, without overpromising capabilities that depend on external systems.

From local control panels to nationwide alerts

Whether managing factory floors, utility systems, or HVAC installations, SMSEagle extends your infrastructure with centralized SMS alerts. The key is understanding that your connected equipment must generate a clear digital signal change for SMSEagle to act.

You don’t need to modify your PLCs or install new platforms. The integration works seamlessly as long as your devices output a recognizable ON/OFF signal. And the rules you configure ensure messages reach the right people with minimal delay.

This targeted, rule-based setup is ideal for mission-critical environments that demand fast, reliable notifications without relying on fragile software layers.

Easy integration for technical and non-technical users

Everything is configured through an intuitive web interface. Technical users can assign specific ports, define text commands, or configure output durations. For less technical users, the simple ON/OFF logic and clear configuration screens make setup straightforward.

The system works best with devices that follow digital logic conventions—those that send a pulse, flip a relay, or light an indicator when an event occurs. That’s when SMSEagle becomes a reliable part of your communication loop.

The focus isn’t on interpreting sensor behavior but responding to the device’s electrical signals.

Alert systems that adapt to your workflow

You can still create sophisticated SMS alert workflows based on your input/output states. Whether sending messages during certain hours, escalating alerts by team, or defining follow-up actions, everything is possible as long as the digital input state changes in a detectable way.

Want to send a confirmation SMS when a machine turns off? Or activate an output when a command message comes from a specific contact? That’s fully supported. Just ensure the hardware signals align with what the system can detect.

This setup avoids false assumptions and ensures reliable, maintainable automation—even in demanding environments.

Built for long-term dependability

Digital inputs and outputs offer a simple yet stable foundation for device control, especially when used as intended: to detect or trigger ON/OFF states. As your hardware evolves, you can quickly update your rules, reassign ports, or expand monitoring without complex integration.

You’ll get dependable alerts, reliable output control, and mobile-ready communication. But always ensure the connected devices produce valid state changes—the strength of this system lies in responding to clear, binary signals.

In industrial and business-critical use cases, that clarity is what makes SMSEagle a trusted automation tool.