3. Installing Windows drivers

If you use Windows on an Arm-based PC, Windows will refuse to install these drivers due to different requirements for digital signatures. You should be able to skip this section and still use the device.

Before you connect your Pololu Isolated USB-to-I²C Adapter to a computer running Microsoft Windows, we recommend installing its drivers. Driver installation is not required on Windows 10 and later, but installing the driver is recommended because it allows you to see the correct product name in the Device Manager instead of “USB Serial Device”.

1. Download the Pololu Isolated USB-to-I²C Adapter drivers for Windows (14k zip) and extract the ZIP file to a temporary folder on your computer. (These files are also available in the “drivers” directory in the Pololu Isolated USB-to-I²C Adapter repository.)
2. Open the “pololu-usb-i2c-adapter-windows” folder. Right-click on “pololu-usb-i2c-adapter.inf” and select “Install”.
3. Windows might ask you whether you want to open the file because it was dowloaded from the Internet. Click “Open”.
4. Windows will ask you whether you want to allow the Microsoft “INF Default Install” app to make changes to your device. Click “Yes”.
5. Windows might ask you if you want to install the drivers. Click “Install”.
6. Finally, Windows will display “The operation completed successfully.”.

COM port details

After installing the drivers and plugging in an adapter, in the “Ports (COM & LPT)” category of the Device Manager, you should see a COM port for the adapter named either “Pololu Isolated USB-to-I2C Adapter” or “Pololu Isolated USB-to-I2C Adapter with Isolated Power”, depending on which product you have.

You might see that the COM port is named “USB Serial Device” in the Device Manager instead of having a descriptive name. The port will still be usable, but it will be hard to tell if it is the right one because of the generic name. We recommend fixing the names in the Device Manager by right-clicking on each “USB Serial Device” entry, selecting “Update Driver Software…”, and then selecting “Search automatically for updated driver software”. Windows should find the drivers you already installed using the instructions above, which contain the correct name for the port.

If you are using Windows 10 or later and choose not to install the drivers, the adapter will still be usable. To tell which “USB Serial Device” in your Device Manager is the adapter, double-click on each one and look at the “Hardware Ids” property in the “Details” tab. If you see USB\VID_1FFB&PID_2502 or USB\VID_1FFB&PID_2503 listed, that COM port is the adapter.

If you want to change the COM port number assigned to your adapter, you can do so using the Device Manager. Double-click a COM port to open its properties dialog, and click the “Advanced…” button in the “Port Settings” tab.