Connecting a Computer to Your DCC System

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Connecting your computer to your DCC layout will provide many benefits. The first, and perhaps fastest noticeable benefit is programming of decoders. After your computer is connected to your layout, you will need some DCC Software.

Adding a computer to the layout will enhance your DCC experience in a number of ways. From decoder management to automation and operations software, the addition of a computer will expand the possibilities of Digital Command Control.



There are many benefits of connecting your computer to your DCC system. Perhaps the most noticeable, and fastest to do is to use it for programing decoders, mobile and stationary. With software, such as the free JMRI software suite, you can quickly, and easily program decoders without learning all the complicated configuration variables of your decoder.

You can also perform automation of your layout, control signals automatically, as well as a display of your layout with train locations.

Of course, this does involve more wiring, and slightly more costs. For example, you will need to connect your DCC to your computer (see below). You will also need to setup up block detection so that your computer will know where trains are. If you are using a DCC system with transponding, some software applications can not only tell that a block is occupied, but with what rolling stock.

Connecting your computer

You will need to connect your DCC system to your computer through a computer interface (find your system below). To do this, you will need to follow your systems documentation on data bus wiring.

Most computers with a USB or serial port will be adequate. JMRI software is available for Apple's OS X, Linux and Microsoft's Windows operating systems. Some interfaces may be USB only, and if the computer lacks a USB port, a Serial to USB adapter may be the answer, or if possible, installing a USB interface card. There are some issues surrounding older versions of Windows and USB, so some research may be needed prior to moving toward interfacing a computer to your DCC system.

Not all USB to Serial adapters are created equal. Some may not work correctly with the USB device or the serial port.

The typical 25 pin serial port uses almost all the pins, some for purposes other than data communications. The 9 pin version uses all the pins, so if some signals (such as DCD, CTS, DTR and DSR) are missing, it causes problems.

The best USB to Serial converters are based around the FTDI Chipset. ESU and RR-CirKits offer adapters which will work.

ESU offers a 1.8 USB connection cable, and warns that older ESU USB adapters may not work with Window7. It has both D-sub and USB connectors. It is USB 2.0.

Manufacturer:RR-CirKits|RR-CirKits offers a similar product with an adapter for 25 pin D connectors, should you need it.

Computer Interfaces

Consult the Computer Interface List for available devices compatible with your DCC system.

Troubleshooting an Interface Device

A typical complaint is that the computer cannot find the interface to your DCC system. Frequently the culprit is a old device lurking in your operating system that is confusing your new device driver. To clean up old device drivers, search the web for, "removing old device drivers from <your OS>", then follow those directions.

NCE USB Issues

Many use an ESU cable built around the FTDI chipset with their NCE Power Pro. The UN8-BE from RR-CirKits is similar.

Counterfeit Devices

Sometimes a USB to Serial interface does not work. Of the the reason is that the USB interface IC in the adaptor is a counterfeit version. FTDI did update their drivers, and those drivers will not work with an IC that isn't made by FTDI. In many cases the drivers for MS Windows 10 don't work with counterfeits.


Some material comes from the JMRI website. If you are interested in using the JMRI suite of tools, visit their website to see what you need. JMRI Website

See also