Product

Test system behavior with digital twins.

Connect your software to virtual devices, exercise normal and failure states, and inspect the response. Use SPX before hardware arrives or alongside your physical setup.

See a working example Install SPX

A working example

Write a setpoint. Watch the temperature respond.

A virtual HVAC unit receives a BACnet command. Its supply-air temperature changes over time, so your software can test the response.

SPX HVAC chart with a 19 to 22.5 to 19 degree setpoint pulse, a gradual temperature rise and a cooldown on a shared Celsius axis.

Flexit Nordic HVAC library model. Setpoint in teal, supply temperature in red; time in seconds. Paused after heating and cooling for inspection.

1. Run the model
Start the library HVAC model as a virtual BACnet/IP device.
2. Send a command
Use your BACnet client to write 22.5°C and enable heating. Read both values back.
3. Check the response
Watch the supply air warm up. Restore 19°C and disable heating to follow the cooldown.

Run the BACnet walkthrough

When to use SPX

Keep testing when hardware limits you.

Use a controllable virtual environment at every stage of development.

Before hardware

Start integration early

Connect software while devices or complete setups are still unavailable.

Alongside hardware

Scale beyond the lab

Run parallel tests while physical equipment is busy with other work.

Beyond hardware

Exercise difficult states

Test faults, extreme inputs and recovery without disrupting real equipment.

Use cases

Choose the problem you need to solve.

Follow a workflow for your engineering task.

Embedded and integration

Test software before devices arrive

Connect firmware or client software to virtual devices with live state and protocol behavior.

Find interface, timing and reconnect problems earlier.

Embedded software testing

Automation and commissioning

Rehearse system interactions

Connect virtual devices and controllers to exercise building or industrial automation logic.

Check interactions before onsite commissioning.

Virtual commissioning

QA and reliability

Check failure handling

Apply controlled faults and boundary inputs, then inspect state, values and logs.

Repeat difficult conditions and compare the response.

Scenarios and fault validation

Development and CI

Automate repeatable checks

Drive the same models through Python tests and CI workflows.

Turn a useful experiment into a regression check.

Python and CI workflows

How it works

Create. Connect. Test and repeat.

Start in the UI and automate when you are ready.

Step 01

Create and run

Choose a library model, describe one to your AI agent or define it in code. Start an instance.

Step 02

Connect your software

Use the model's protocol endpoint and addresses to read values and send commands.

Step 03

Test and repeat

Change inputs, run scenarios and inspect the response. Restore configuration from a snapshot; automate checks with Python or CI.

Watch the smart-building AI walkthrough

See an AI agent connect weather and HVAC behavior in a running SPX environment.

Explore further

Find the detail you need.

Capabilities

Product features

Build, connect, validate and automate.

Explore Features

Connections

Protocol walkthroughs

Client settings, addresses and expected replies.

Choose a protocol

Developers

Models and automation

Start paths, model YAML and developer resources.

Open Developers

Ready to start

Run your first virtual device.

Choose a plan, install SPX and follow the first-device guide to get a result you can check.

Try for Free Read the Docs