> For the complete documentation index, see [llms.txt](https://wecon.gitbook.io/pistudio-manual/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wecon.gitbook.io/pistudio-manual/3.-getting-started/3.5-simulation.md).

# 3.5 Simulation

**Introduction**

The following steps will show how to use simulator in PIStudio.

**Operating procedure of offline simulation**

1. Click \[off-line] to open the simulation window;
2. Check HMI screen in window;

**Operating procedure of online simulation**

![](/files/-Lupi6RMFnnE85fxiku1)

1\) Click \[on-line] to open \[online simulation serial select tool];

2\) Select COM port in PC for link;

3\) Click \[OK] to open simulation window;

4\) Check HMI project in window

{% hint style="info" %}
**Note:**

If HMI project uses Ethernet communication, no need selects any port in online simulation.
{% endhint %}