RESTful API in a PAC!

Just say no to middleware. 

Now Internet of Things applications can securely communicate directly with programmable automation controllers (PACs).


What can I do with a RESTful API to a PAC?

  • Archive I/O and variable data from the PAC directly into Microsoft SQL Server using Microsoft's T-SQL—no OPC or ODBC required
  • Read data from and write data to the PAC from your browser or web-based application using JavaScript.
  • Read or write PAC data using your favorite programming language—C, C++, C#, Java, PHP, Python, and many more
  • Build a mobile application that directly accesses data on your PAC—using Java, Swift, or Xcode 
  • Build a data flow application for communicating with cloud platforms and cloud APIs, using Node-RED and our SNAP PAC Nodes.

For software developers and Internet of Things (IoT) applications, the RESTful API and server allow secure access to PAC Control variable and I/O data in any SNAP PAC standalone S-series or rackmounted R-series programmable automation controller with firmware R9.5a or higher. 

Each controller includes an HTTP/HTTPS server and RESTful API, compatible with any programming language that supports JavaScript Object Notation (JSON). 

See the documented API and get started now on

SNAP PAC with RESTful API architectural diagram


Learn more with these Technical Notes

How do you keep critical control networks safe and still provide useful data where and when it's needed? Find these answers and more in two informative technical notes:

SNAP PAC REST API Tech Note - OT ProfessionalsSNAP PAC REST API and the IoT - for OT Professionals explains:

  • The kinds of data automation (OT) professionals may be asked to provide and why
  • Concepts important to any IoT strategy, like encryption and authentication 




rest_tnote_it_155x200.pngSNAP PAC REST API and the IoT - for IT Professionals explains:

  • How physical things communicate
  • The kinds of data they contain 
  • Current barriers to getting that data—especially from existing sensors and devices that have no IoT capabilities built in





Learn more from these resources         (Ver en español)             

New to the Internet of Things?

Opto 22 Internet of Things

Learn the basics with this IoT Primer.

  • Find out why the Internet of Things is important to every business.
  • Understand IoT challenges.
  • Learn about IoT technologies.

What's edge computing and how does it help solve 3 major problems with IoT applications? Read the Edge Computing Primer

A RESTful API in a PAC is big news that's made industry headlines:

Questions? We have answers...

How can I get the new RESTful API?

  • The RESTful API is a standard feature on all PACs we ship today. See standalone PACs and rack-mounted PACs with the REST API. 
  • Or add it to any SNAP PAC controller dating back to 2007 simply by updating to firmware R9.5a or higher, free of charge.

How do I update my SNAP PAC controller for the RESTful API?
Follow along as our blog post walks you through the steps.

Does the RESTful API replace a controller's existing methods for exchanging data?
No. All other methods continue to be fully supported, including EtherNet/IP, Modbus/TCP, OptoMMP, OPC, and more. See the controller comparison chart.

How does the RESTful API help automation and IT professionals in my organization?
Manufacturing operations personnel can use the PAC's RESTful API to transfer data from manufacturing assets directly into IT systems like databases and the cloud, without having to use protocol converters, OPC servers, or gateways.

IT professionals can use the tools of their choice to develop software applications for manufacturing, asset utilization, predictive maintenance, and more. With the RESTful API to PACs, old tools like drivers, converters, and licenses are a thing of the past. 

Need some help with your IoT project?

IoT Certified OptoPartner logoAn IoT Certified OptoPartner has skills and experience in both automation and information technology—controls and programming.

If you could use some help planning or implementing a new project, contact one of our IoT Certified OptoPartners. They'll be glad to fill in where you need assistance. 

Looking for more technical support?

Visit for the complete SNAP PAC REST API, steps to get started, and examples. 

Learn how to read from and write to an Opto 22 SNAP PAC programmable automation controller via the PAC’s RESTful API, using Visual Basic for Applications (VBA) with Microsoft Excel. In this way you can securely share I/O point and variable data in your SNAP PAC controller with an Excel spreadsheet.  Download: SNAP PAC RESTful API to Excel Spreadsheet Technical Note.

See how to read data from an Opto 22 SNAP PAC programmable automation controller and place it in a Microsoft Access database. Download: SNAP PAC RESTful API to Access Database Technical Note.