The connection from the NCE PowerCab to notebook, laptop or any computer for that matter is very simple using a USB port not Serial/Com ports.
NCE PowerCab DCC Starter System
NCE USB interface module (Purchased Separately)
NCE curly cable (Supplied with PowerCab)
NCE PowerCab Panel (PCP) (Supplied with PowerCab) This is the panel that connect the DCC system to your track.
USB standard printer Type A to Type B cable (Purchased Separately)
Notebook, laptop or any computer with at least 1 USB port.
1. UBS printer Type A to Type B cable plugs into a USB port on your notebook, laptop or computer. They all have at least one USB port on them these days. The other end plugs into the NCE USB interface module that should be already set up on your layout.
2. NCE curly cable plugs into the bus connector on the NCE USB interface module.
3. The other end of the curly cable plugs into the unused port on the NCE PowerCab Panel (PCP). You should already have the flat cable plugged into one port and the other end in PowerCab Throttle.
4. Start up your computer and it should automatically assign the USB port you are using with a COM# number.
5. Turn on the NCE PowerCab
6. Open JMRI, go to the Edit Tab and select Preferences.
7. On the Connections Tab select
System Manufacturer = NCE
System Connection = NCE USB
Serial Port = COM3 (There could be more than one COM# so start with the first one and keep changing until one works)
USB Version = V7.x.x
System = PowerCab
Connection Prefix = N
Connection Name = NCE
8. Save your changes and shut down JMRI but leave the NCE PowerCab still on.
9. Start up JMRI again and down the bottom of the JMRI page will tell you if your are online in green print.
10. If still offline then go back and change the Serial Port COM number if there was more than 1 showing.
Now you will have JMRI communication with your NCE Power Cab to your track.
From there you can advance to have JMRI run your locos via WiFi using a tablet or mobile phone as a throttle for complete wireless control.
Hope this helps