Frequently Asked Questions (FAQ)

If you have a problem in using your SPROG then please check the list of Frequently Asked Questions to see if you can resolve the problem. If you are still experiencing difficulties then please e-mail us. If you are using DecoderPro then it is usually helpful to include a log of what you are trying to do. Open a DecoderPro command monitor (from the SPROG menu) log to a file and then try repeating the operation you were attempting, Send the log file to us.

If you are a new user then please ensure you have read the User Guide which can be downloaded through the link on the product page.

Section I - General Questions

Which SPROG should I buy?

Please note that the SPROG 3 does not replace the SPROG II. Both models will continue to be available.

For everyday decoder programming we recommend the SPROG II. This will also allow control of a small layout, e.g. 2 - 3 modern OO locos or more in N gauge, with up to 1 Amp output.
The SPROG 3 is higher power version of the SPROG II and is intended for control of larger layouts but retains the programming functionality of the SPROG II.
The SPROG Nano is a low cost interface to drive a DCC booster from the USB port of a PC or Mac. It has no programming track capability but can still be used for "ops mode" or "on the main" programming. A separate DCC booster is required with the SPROG Nano.

What software do I need to use a SPROG?

We recommend DecoderPro for the simple reason that is what we have the most experience with.

SPROGs may be supported by a number of other software packages including Rocrail and RR&Co. Please contact the suppliers for more details.

Where can I buy SPROGs?

You can buy direct from us through this website or from a growing list of UK and international dealers (see our dealer list ).

How do I know what firmware version my SPROG has?

Use the firmware version utility under the SPROG menu in DecoderPro.
Alternatively, you can use a terminal emulator program such as TeraTerm to connect to the SPROG and type ? followed by carriage return.

Section II - Other Operating System Support

Can SPROGs be used with Linux?


Drivers for the SPROG II USB which uses the FTDI chipset are included with the major Linux distributions. If the drivers are not included in your kernel they can be downloaded from the FTDI website <.p>

Some notes from a SPROG user can be found here.

SPROG IIv3, SPROG 3 and SPROG Nano will appear as tty_usb devices and should be supported by all major distributions.

Can SPROGs be used with MACOS?

Yes. Our US distributor hosts a very useful online installation guide

Can SPROGs be used with a Raspberry Pi?

Yes. Simply connect them to a Pi USB port as with any other Linux system.

Section III - Power Supplies

What sort of power supply do I need for a SPROG?

The SPROG Nano takes power from the USB cable and requires no power supply.

All other SPROGs require regulated DC power supplies.

The SPROG II should be used with a power supply of 12 - 15 Volts capable of supplying at least 1 Amp, otherwise the over current protection feature will not operate correctly.

The SPROG 3 should be used with a power supply of 12 - 18 Volts capable of supplying at least 2.5 Amp, otherwise the over current protection feature will not operate correctly.

Can I use my old DC throttle/transformer/controller as a power supply for a SPROG?

Probably not, and it is not recommended.

Many old DC powerpacks/throttles/transformers/controllers do not provide smooth DC and are unsuitable for use as a power supply for a SPROG. You may experience erratic operation, or even damage to the SPROG as a result of using such a unit as a power supply for a SPROG.

Section IV - Specific Decoder Problems

Which decoders has the SPROG been tested with?

Please consult the compatibility list.

What can I do if my decoder is not supported by DecoderPro?

New decoders are being added all the time by users and developers. If you are fimiliar with XML (or wish to learn) then you could write your own definition file. More details on this procedure can be found on the JMRI webpages. Another possibility is to ask on the  jmri users group if anyone has already written the appropriate definition file.

Very often it will be possible to select a similar decoder from the same manufacturer. Failing that, the NMRA standard decoder can be selected to allow access to all of the common CVs.

Problems with ZTC decoders

Some ZTC decoders do not respond correctly on the programming track with a SPROG in its default mode. This is due to the decoders expecting DCC bit timing which is out of tolerance. To get around this you need to use the SPROG console in DecoderPro to enable ZTC mode.

Unfortunately, it has been found that, even with this fix, ZTC202 decoders do not work with the SPROG.

Problems with Digitrax decoders in direct mode

Very early versions of the SPROG II firmware have a bug which prevents Digitrax decoders being programmed in direct mode. To work around this bug, select paged mode programming in DecoderPro when programming digitrax decoders. This is fixed in SPROG II version 1.4 firmware, and later, and in all SPROG IIv3, SPROG 3 and Nano firmware.

Section V - Using DecoderPro With SPROGs

How do I use DecoderPro with SPROG?

To configure DecoderPro to work with a SPROG you must select SPROG DCC as the manufacturer in the connection preferences and then select SPROG for programming operations or SPROG Command Station to use as a command station.

Does the SPROG support the DecoderPro throttle?

Yes but you require SPROG II version 1.3 or later firmware or any SPROG IIv3, SPROG 3 or Nano for the function buttons to operate correctly. You must turn the track power on and off manually using the Power Control under the tools menu. Any programming operation will always leave the track power turned off.

Can a SPROG be used as a computer controlled command station/booster?

Yes, select SPROG Command station as the conection preference in DecoderPro and use up to 15 on screen throttles.

What does "Error timeout talking to Command Station" mean?

This is often caused by a mismatch between the COM port selected in DecoderPro preferences (edit menu) and the COM port to which the SPROG is actually connected.

USB SPROGs use Virtual COM port drivers. On Windows machines, right click on "My Computer" then click Properties -> Hardware -> Device Manager. Click + next to "Ports (COM & LPT)" and note the COM port number assigned to SPROG. Ensure this is selected in the DecoderPro preferences.

Section VI - Using SPROGs with sound decoders

Can I use a SPROG to program new sounds into my sound decoder?

No. There is (as yet) no standard way of programming new sounds into sound decoders. You must use the decoder manufacturers proprietary sound programming device.

Will SPROG II work with Broadway Ltd sound equipped locos?

The short answer is yes, but the full answer is a little longer. These locos are notorious for the inrush current when they are powered up. The SPROG has been demonstrated to cope with this so long as the power supply is of sufficient capacity and a low value current limit resistor is fitted in one of the programming track leads.

Will SPROG II work with BLI Blueline decoders?

Yes but you should use the SPROG console in DecoderPro to enable Blueline compatibility mode.

Will SPROG II work with QSI decoders?


What about other sound decoders?

No problems reported!