If you want to connect the PLC to the computer, you need a transmission port first. When the PLC is connected to the computer, right-click My Computer and select Manage.

In the pop-up computer management window, select Device Manager.

Check the number of com ports used by the communication line and remember the port. In this case, it is com 10.

Return to the PLC programming software, select the "Online" menu bar, and select "Transmission Settings" from the drop-down menu.

In the "Transmission Settings" dialog box, you need to set the "serial USB" interface, and double-click the button shown in the red box below.

Then set the com port to com 10 in the pop-up port setting interface.

Finally, click "Communication Settings". If the connection with PLC is successful, click OK, and then write the program into PLC.