The simulator drives your layout.

NCE: what you need

• An NCE system: Power Cab, Power Pro or SB5.
• The NCE USB Interface, NCE part 524-0223, about $45 at any NCE dealer. It sits on the cab bus and lets the computer send commands.
• For the other direction, your handset driving the screen, the modelrailsim DCC Sniffer from the store; see Real controller.
• A 6-wire cab-bus cord (RJ12). One comes with the interface.
• A USB cable for the interface: USB-B on its end, USB-C or USB-A on yours.
• Chrome, Edge or Brave on a Mac, Windows or Linux computer. Phones and other browsers can't open serial ports.

NCE: plug it in

1. Leave the Power Cab handset in the panel's left jack with its flat cable. It is the command station; it stays.
2. Cab-bus cord from the panel's right jack to the USB Interface.
3. USB cable from the interface to the computer. The interface takes its power from the cab bus, so the panel must be on for it to appear.
4. Handset on its normal loco screen, track power on. In a menu, the Power Cab ignores commands from the computer.
5. No driver is needed on current Macs and Windows. The DIP switches on the interface can stay as they came; the simulator finds the right speed by itself.

Digitrax: what you need

Coming. The simulator will talk LocoNet through a Digitrax PR4: USB on one side, LocoNet on the other. Not the PR3, which has no driver for current Macs. The same card, the same Real locos and Real turnouts lists; only the box on the desk changes. Until it ships, a Digitrax layout can still drive the screen through the Real controller, which works with any DCC system.

Connect

1. Open the simulator and the Real layout card: Shift + H, or the Real layout button in the dock.
2. Press Connect and pick the port. It is the one named after the serial chip, usually "CP2102 USB to UART Bridge". The card shows the interface's firmware when it answers.
3. Under Real locos, type a loco's DCC address and press Add real loco. It joins the Locos list marked REAL and lands on the cab. Tick "Also put a twin loco on this board" first if you want a sim loco to stand for it.
4. Under Real turnouts, give each turnout the accessory number its decoder answers to and tick On.
5. Drive from the on-screen Power Cab, the keyboard, or ask the Conductor. Every change goes out to the rails.

Good to know

• Set the handset down while connected. The USB Interface can't tell the computer what the handset does, so the simulator is the only throttle. If you want the handset to drive the screen too, that is the Real controller.
• Forward and reverse swapped? The real loco sits the other way round from the direction the sim calls forward. Tick Reversed on its row.
• Stop all e-stops every real loco. Closing the tab or unplugging stops them first where it can.
• Nothing is ever written to your decoders, and the card's log stays in your browser.

If it doesn't answer

• "The interface answered nothing." Panel off, cord not clicked in, or the cord in the wrong jack; the interface's LED should be lit. If it is lit and still silent, the interface's processor is stuck waiting for the rest of a command that got cut off (a closed tab, a program fighting over the port): unplug the cab-bus cord from the interface for five seconds, plug it back in, Retry.
• "Port in use by another program." Another tab, or JMRI, holds the port. Close other modelrailsim tabs and JMRI, then Retry.
• No port in the picker. Bluetooth ports only, or nothing: the USB cable is charge-only, or the interface isn't plugged into the computer.
• Commands acknowledged, loco doesn't move. The handset is in a menu: press ESC until it shows the loco screen. Check the track power light on the panel.