> For the complete documentation index, see [llms.txt](https://kb.linknlink.com/isg/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kb.linknlink.com/isg/using-isg/add-ons/optional-utility-add-ons/serial-port-viewer.md).

# Serial Port Viewer

## Prerequisite:

The iSG system firmware version must be 20124 or higher.

You can refer to this guide for upgrading the iSG version: [iSG Firmware Updates](https://kb.linknlink.com/isg/settings/firmware-updates/isg-software).

## Instructions for Use:

1）Turn on the iSG, and in the left navigation bar of the iSG, find "Add-Ons" → "Serial Port Viewer". Here, you can view the serial port information connected to the iSG's USB port. 

<figure><img src="/files/4edm95wYmNIyGpI0bgVm" alt=""><figcaption></figcaption></figure>

2）For example, when we plug a Z-Wave dongle into the USB port on the side of the iSG, clicking here will show us the automatically detected serial port information:

<figure><img src="/files/PM9XTPKXXQtEkshr7uBS" alt=""><figcaption></figcaption></figure>

<mark style="color:red;">**Note：**</mark> If you plug in the USB dongle, no information is displayed in the details page on the right. You need to click on any other Add-on, and then click on the Serial Port Viewer Add-on, and the USB dongle information will be displayed. If still not, please contact us via [discord channel](https://discord.gg/bYnDNdMsnS)