When setting up external communication with devices via RS232 on Window you need to know which COM port to send / receive commands on.
There are a couple of ways to find this:
1. Check the 'Device Manager' app on your Windows machine and check the ports under Ports (COM & LPT)
2. Check the embed application settings by opening the settings panel, entering the password and click on 'Settings'.
Then scroll down to the Serial/RS232 devices section and you'll see the available COM ports being used:
Once you've found the COM port for your device you can continue to setup your RS232 device.