Virtual Input » History » Revision 2
Revision 1 (Adam Klama, 06/21/2026 02:35 PM) → Revision 2/3 (Adam Klama, 06/21/2026 03:22 PM)
# Virtual Input ## Overview A **Virtual Input** is a value you set **from the datalogger over USB**. The datalogger presents a set of **sliders**; each Virtual Input is one slider you can drag to set its value live. Use it to inject a value for **testing** and tuning — exercising logic that consumes an input without the real sensor connected. ## Prerequisites - The **datalogger** connected over **USB** to move the slider. ## Add it in the app 1. Add a new input and choose **Virtual Input** as the type. 2. Give it a clear **alias** (e.g. `Test Setpoint`). 3. That's it — the value is driven from the datalogger slider. ## Settings reference This input has no type-specific settings — its value is set from the datalogger slider over USB. See Common settings below. ## Common settings Virtual Input also uses the shared setting — alias. See [Common IO Settings](Common_IO_Settings). Settings](../Common-IO-Settings.md). ## Example — test setpoint 1. Type **Virtual Input**, alias `Test Setpoint`. 2. Reference `Test Setpoint` wherever you would normally use a measured input — for example as a term in a [Compare Input](Compare_Input) Input](Compare-Input.md) or [Math Divide Input](Math_Input). Input](Math-Divide-Input.md). 3. In the datalogger, drag the `Test Setpoint` slider to different values to exercise the logic that consumes it. ## Troubleshooting - **Value never changes:** the datalogger isn't connected over USB, or the slider hasn't been moved. - **Other IO don't see it:** check they reference the correct **alias**. ## Related - [Constant Value Input](Constant_Value_Input) Input](Constant-Value-Input.md) — a fixed value that is not written at run time. - [System Input](System_Input) Input](System-Input.md) — an internal value produced by the controller.