Digital Direct for Windows





01 January 2017

In DDWServer version 0.86 several bugs were fixed which concerned the compatibility to Kolopler and rocrail. Moreover, the KeepAlive function of the tcp-socket now works correctly, so that DDW terminates dead connections to clients.

30 September 2014

Finally, a new version of Gplan is ready for download. Similar to DDW server the current version 0.80 is a port of the last Gplan version 0.70 on the DotNET-Framework. Unfortunately I have not managed to implement all the features found in the latest version. The joystick support, the text input in the track layout and the copy-paste function when creating the track layout is missing. I hope I will finish these functions soon. Please, to me all bugs quickly so  that I can fix the problems. Unfortunately I can not test Gplan on any computer available, however,  Gplan run stable on all tested PCs. The NET Framework 4.0 is required to run Gplan. Gplan stores the configuration data and track layouts no longer in the program directory but in a separate directory which is created during installation in "C: \ Users \ username \ AppData \ Roaming \ Gplan".
I would like to thank Jetbrains for a free license of "Resharper". The program is amazing and makes programming much easier.
As usual, you can download the code and the precompiled program at SourceForge.

31 March 2014

Over a year has passed since the last update. Although in the current version, some interesting new features have been incorporated , there are still construction sites in DDW . One relates to the phenomenon that obviously not all Märklin decoder work properly with the new DDW version. I have not been able to find the reason for that problem.
Since the release of the new version of Gplan will still take some time, I have released the last version with a new installer, so Gplan can also be installed on Win7 computers.

The following items were fixed and/or added:
- DDW has got a plug-in interface . This makes it possible to write additional programs as plug-ins. Realized is the access to the configuration variables as well as the command and info channel communication with DDW at the moment. This could be, for example, a web interface or a client for the control of DDW. Basis of this extension is the Managed Extensibility Framework (MEF , % 28v = vs.110 % 29.aspx ).
A short guide to creating plug-ins is available for download.
- The internal architecture has been changed so that almost no static classes are implemented.
- The interface to the HSI- S88 feedback modules is now finally finished . Modules with RS232 or USB port can be used. The USB interface can only be activated once. Unfortunately, I was not able to solve this problem. For a second initialization of the USB interfaces HSI88 DDW must be restarted. If someone finds a solution to this problem , I would appreciate information on this.
- A minor bug was fixed in the routine to switch power which meant that Rocrail has not worked together with DDW, which is now fixed. Rocrail can now be used as a client for DDW.
- The RTS line  at the start of DDW- depending on configuration - can be switched to either high or low.
- The short-circuit detection on the DSR line has been updated - thanks to Jens Müller.

18 March 2013 It is time for a DDW update. I am very grateful for the support of several users who helped to fix functions and to add new properties. The most important addition might be the implementation if 28 !! functions for NMRA/DCC decoders which was written by Michael Meschke. In this context the 'NmraPacketPool' was rewritten. Moreover, 'GET 0 SESSION' was implemented. In addition, several bugs were fixed: termination of devices during client disconnect, display of the program version and reaction to a short (thanks to Ralf Greinert and Jens Muller!).
11 May 2012

After the rainy days here in Berlin it is time for a new update! The following changes are incorporated into the new DDW-Server version 0.83: DDW-Server stores the configuration file and the log files in a directory which is created during installation at .."\User\Application Data\DDWServer". A bug in the NMRA/DCC translation algorithm is fixed. Furthermore, the error message during the start of the program that the serial port cannot be assessed is corrected.

21 December 2011 I wanted to release the new version of DDW-Server 0.82 before Xmas! Compared to the last version several small bugs were fixed. DDW should now work together with Gplan! Associated with the current version is a change to DotNet Framework 4.0. In addition, I have added a installer program so that DDW-Server can be easily installed and deinstalled. The c# source code can be obtained from the SVN repository of the DDW Sourceforge website.
16 July 2011

The new DDW version 0.81 solves hopefully some of the problems which were experienced with the first version after change from c++ to C#, e.g. the internal Timer function for timing of data packet output, which was previously in a separate DLL, is now integrated in the code. Therefore, latencies that were caused by calling the DLL could be minimized. The mode with improved timing for solenoid decoders works fine with original Märklin (K83) decoders. Whether it works with decoders that use PIC has to be evaluated.
Apart from optimizing signal generation other features were improved: Busses are can be configured according to your needs. In practice you could operate DDW with only two busses: One "Controller Bus" (bus 0) to control server functions and one Device Bus which can be chosen between 1 to 12. The disadvantage of this configuration is that the addresses of the different protocols are not allowed to overlap. e.g. a loco with a NMRA/DCC decoder can not operated with the same address as a loco with a MM-decoder and vice versa. It is now possible to use DDW with programs which expect all devices on one bus, such as JMRI ( In addition the communication between Gplan und DDWServer should work again.
I cannot provide a programming of decoders with the present DDWServer version. This is due to a lack of appropriate hardware. The code for programming of NMRA/DCC decoders is in parts already written but not really tested. So if anyone wants to help me out I am happy to provide a version for completing the missing code parts. This should be quite easy to complete since  C#-Visual Express can be downloaded from Microsoft.
DDW is prepared to work an Linux with Mono, however, the latest code changes are not adapted for Linux so that DDWServer will not work on Linux at this time.
I want to thank Dieter Albert who suggested many improvements and helped me to visualize the data packets with his memory oscilloscope.
An installation of the program is still not necessary: just unzip the downloaded packet und start the "DDWServer.exe" file. The installation of the giveio.sys-driver is still not necessary.

28 July 2007 Holiday season is coming and before it starts a new update of DDW-Server is ready:
- Sven Schlender has implemented the DNS-SD into DDW-Server, a way of using standard DNS programming interfaces, servers, and packet formats to browse the network for services. However, "Bonjour®" has to be installed to use this function.
- SRCP has received an official port by the IANA : 4303. It is recommended to use this port in all installations.
28 February 2007 During operation of 605xEmu version 0.3 several running time problems turned up which were the reason to complete rewrite major parts of the Emu code. With the patience and numerous tests of Rainer Hoefs the new version 0.4 finally works with most common railroad controller programs. Some problems turned up in the setup menu of the SRCP busses. While the Emu is operated with DDW the default settings should not be changed. However, the virtual serial driver must be installed anyways.

20 February 2007 Several users have experienced bugs in DDW. At the same time a couple of suggestions were issued which I have tried to realize. Therefore, a new release of DDW seems appropriate. The following issues were improved/corrected in the 0.77 version:
- Info messages for the GL-bus show the correct protocol version
- The names for the serial interface were not correctly loaded when DirectAcces was switched off, this problem was fixed.
- A new setup option was created to enable backward compatibility of the MM protocol with older versions, this seems to be important for programming some decoders.
- Signal generation for DirectAccess = Off modes was rewritten. For most PCs there should be no difference whether DirectAccess is switched Off or On. It will be interesting if DDW can be operated with USB->RS232 interfaces. I would greatly appreciate if you could report you experiences.
- The stat of the S88 feedback contacts is now logged also.
- An improved timing algorithm for solenoid decoders as suggested by Marco Roede ( was implemented. Hopefully, operation of turntables may be possible.
02 July 2006

The summer holidays are coming – isn’t that a reason for an update! Andreas Maercz ( has done some work on the S88 bus. In SRCP 0.8x mode all 4 busses can be used and he also wrote a “generic” initialization. Thanks for the help! The work on the programming bus is not yet finished I hope it will be finished in the next version.


17 March 2006 I want to submit a new version of DDW server: Pavel Gulich has written a Czech translation which has been included. The new version can also be operated with the HSI88 interface (only SRCP 0.82 mode). S88 modules on the parallel interface can be used in parallel. Initialization is done with “INIT 12 FB HSI88”, termination of communication with “TERM 12 FB”. Since the HSI88 interface can be used together with the S88 bus addresses from 497 up are used – depending on the number of S88 busses. Thanks to Fred Stevens who had helped me out with the HSI88 interface und thanks to Frederik Safströmer who hat tested the new version.
To improve management of source code I have started a cvs repository at where the actual code can be obtained. A suitable client would be Tortoise-CVS. Eventually, the whole download area will be moved to .

13 February 2006

Lasse Schöttner has finished his Client 'Lassebahn' which also provides an interface for programming of decoders, e.g. LD-W-1-decoders. 'Lassebahn' was written in Java.


23 November 2005

After some experience with the previous DDW-Server version (0.73) several issues came up which are fixed in the new version 074:
- Initialization in SRCP 0.8x mode of the S88 interface on Win98 OS was fixed
- Sven Schlender provided code for use of inverted signals on the S88 Bus and added a new error code if the server is not connected to the serial port
- An info message “POWER OFF” is send if a short occurs (only SRCP-0.82-mode)
- Problem with short detection while DSR is set to inverted is fixed

05 May 2005

In the last few months I rewrote Gplan in Borland Delphi. The reason was that the components written by Roman Lauer were difficult to compile with CBuilder and porting to Linux seems .easier in Delphi since Kylix3 CBuilder has many problems. With help of Roman’s components Gplan now can be operated also in SRCP 0.82 mode. The problem with placing text on the layout is solved. Gplan has now a central clock which can be driven either by the PC or DDW-Server. In addition, I have created a synchronization function for the solenoids and the feedback contacts. A French translation was provided by Didier Gasser Morlay.

I’m quite happy that I also finished the first version of a 605x emulator. With the Emulator-605x non-SRCP compliant programs (e.g. Railware, WinDigiPet) can be used together with DDW Server on the same PC. Emulator-605x uses a virtual serial port which has to be installed also. Emulator-605x translates commands for Marklin/ Motorola decoders into SRCP information and sends it to DDW Server and at the same time it sends S88 feedback information to the controlling software. It is possible to use NMRA/DCC decoders, however, due to the restriction of the interface only 14 speed steps and 80 loco addresses are allowed.


06 March 2005

A new release of DDW Server is ready:
- Tom Borrmann has implemented the service functions for SRCP 0.82 mode and changed code of the READ command
- a bug in the Info mode unit resulted in incomplete message generation if more than one info client connected to DDW Server
- Roman Lauer gave some advice how time server function could be realized more stable
- Paul Limpens suggested that the RTS-line stays off during normal operation and is only activated in service mode.

01 January 2005

I have compiled a new version of Gplan. A problem which occurred during operation with joystick is fixed now. Moreover, I have fixed some broken links.


22 December 2004 Just in time before Xmas Holger Seider has finished a new version of RAILYPLAN: Several bugs have been fixed (thanks to all users). In addition, 20 loco icons are available and RAILYPLAN has been translated into Italian. An IR remote control function has been implemented into RAILYPLAN, the necessary hardware is minimal. Thus, locos, solenoids and routes can be operated by remote control.
17 December 2004 I have decided to upload the DDW-Update before Xmas:
DDW-Server version 0.72: Compared to version 0.71 the program memory allocation was optimized and several memoy leaks were localized and fixed. Therefore I strongly recommend an update of version 0.71 !!!
Gplan version 0.63: a) popup messages for the Gplan elements during layout design are now available. b) Paul Limpens has written a Dutch translation. c) The font properties of each text label can be separately chosen.
Roman Lauer written a new version of his MoBA Package, it is available from Sourceforge.

01 December 2004 Probably the last DDW servers update of this year: DDW version 0.71
The following changes were accomplished:
1) an error on use of protocol M4, which led to disconnection of the client was fixed.
2) in SRCP 0.82-mode the S88-Bus is now fully functional.
3) A S88-Simulator written by Roman Lauer for SRCP 0.82 mode was integrated. It is activated in the Setup menu and is helpful for the development of client software.
4) Some smaller changes in the SRCP 0.82 mode, in order to improve the conformity to the SRCP protocol were performed.

5) Paul Limpens has provided a Dutch translation.

03 October 2004 A new version of DDW-Server is available: version 0.70!
1) Lars-Eric has written a Swedish translation. Thanks!
2) Tom has done some fine tuning on the READ-command. Tom told me that he experienced no problems with acknowledgement anymore. Toms uses a detector which can be found on his homepage and which is only slightly changed compared to the detector described by Torsten Vogts on the DDL homepage.
3) The programming of loco decoders had a bug which is fixed now. Thanks Tom!
4) Kay Wolf improved code for emergency stops
5) In case multiple clients were connected to DDW-Server some peculiarities occurred. Thanks to Roman Lauer who was patient with me and analyzed the problems merciless.
6) In SRCP 0.82 mode feedback events are still not automatically detected by the server. This is only of importance if you select info mode. However, with GET you can poll information as before
. I hope with the next version this problem can be solved.

27 June 2004

Before I go into summer vacation I have finished an update of DDW server and Gplan:
1) Luis has translated DDW server into Spanish, thank you.
2) Tom has implemented the "READ" command and also optimized the timing for detection of feedback. Reading of whole registers is now possible with only one command which speeds up reading information from decoders since it is not anymore necessary to test each bit with the VERIFY command. The syntax is comparable to the WRITE/VERIFY commands. Since the feedback information has been not defined in the SRCP protocol Tom has defined the following: 0 - Direct mode not supported, 1 – read was successful, 2 – no feedback hardware detected.
3) All further changes are related to SRCP 0.8x-mode, SRCP 0.73-mode should be untouched.
- The most important issue is the change from SRCP 0.80 to SRCP 0.82 protocol version. This will have no consequences for users, however, for developers is means that software which ran with DDW server 0.68 well will do not run with DDW server 0.69 anymore: e.g the Power device will not be controlled on bus 0 but on any other bus (TIME and SESSION are still controlled on system bus 0). I want to thank especially Roman Lauer who tested any new compilation of DDW server and helped me with several important advices and ideas.

1) Luis has provided a Spanish translation for Gplan as well.
2) The restriction to have only 8 feedback ports for each feedback device has been corrected to 16. In addition a new menu item in the options menu offers a more comprehensive configuration of the feedback modules.

28 April 2004 A small update: Gplan is now available with Swedish language support. Thanks to Lars-Eric! If you want to help me with other languages, please mail me!
I wanted to pack the DirectX-related code into a separate DLL, however, a lot of problems turned up which I could not solve quickly. A temporary solution: if you want to run Gplan without DirectX support just download the Gplanv061NT-version and replace the original Gplanv061.exe with this file.
04 April 2004 An update of DDW server is available. Two issues are worth to mention:
1) DDW server can now be operated with only DCC/NMRA protocol activated. The previous version 0.67 did not function properly. An error in the signal generation part was the reason for this problem.
2) As a new feature direct access to the registers of the serial port can be switched off. It should be now possible to operate DDW wit PCMIIA-serial cards and USD-serial adapters. Importantly, the "giveio.sys" driver is not necessary while direct access is disabled. This mode is at the present time experimental since e.g. programing of loco decoders is still only possible while direct access is enabled. Please report your experience with this new mode. Thank you.
05 March 2004

A new version of DDW Server has been released:
1) The available help file may help start with DDW Server.
2) A new tab for configuration of DDW Server is available: The refresh interval can be varied. Default value is 25 ms, in version 0.66 it was set to 100 ms and caused trouble with some TAMs decoders (Thank you Michael Geramb).
3) CPU-load is displayed in the main window.
4) DDW Server can be started without main window. DDW Server can then controled by right click on the DDW icon in the system tray.

Peter Keintzel has finnished his client for DDW. It works with SRCP 0.8x! You should visit his website to obtain more information on TRAINer.

18 January 2004

Finally, I finished a new version of Gplan: version 0.60!
Changes are:
1) A joystick interface for DirectX has been added. Now, it is possible to use digital joysticks (e.g. on USB port). Two Joysticks with each time four joystick buttons are available. Button one und two are connected to direction and function. However, two function from f1..f4 can be assigned to button three and four.
2) Language (English and German) can be chosen. (Note: if you are willing to help translate Gplan in to your language please contact me:
Designing of track layout has been improved:

3) Selected elements are marked yellow. They remain active as long as another element has been selected or the element palette has been right clicked.
4) Parts of the layout with several elements can be moved freely on the layout area. Elements to move are selected by clicking on the elements with the shift key pressed and appear now outlined in red. The selected elements can be moved with the mouse while the shift key and the left mouse button are pressed. The elements renain selected until you click somewhere on the layout (without shift key!).
5) An 'assistent' shall help you with the first steps in Gplan Enjoy it!




16 November 2003

Several people have asked about installation of the 'giveio.sys'-driver. To make installation more comfortable I wrote an installer program which you can find on the download page.
The actual DDW version 0.66 is now available as Windows service. You can install DDW-Server as service under Windows NT/2000/XP. You will find also an installer program.

Roman Lauer has provided a new version of his tools MoBa package and asks for reports.


02 November 2003

The GET command branch did not work properly, the problem should be solved. The information given back by the server to the clients on command and info channel is now SRCP conform.


04 October 2003

Kay Wolf has written a client to program Uhlenbrock and Piko decoders.


28 September 2003

Holger Seider has finished a new version of Railyplan 1.2 with many nice improvements.


16 September 2003

The problems with creation of new track layouts are solved. Sorry for the inconvenience.


14 September 2003

Gplan has some new features: You can add text to the track layout, an emergency stop botton (red button) stop all locos immediately and with the switch button (yellow Button) e.g. lights can be switched. Gplan has a help function, although it is in German only. The refresh of of function icons has been improved.
The new DDW-Server Version 0.65 displays model time if the TIME function is activated. In addition, the problem which caused an error warning in some cases has been solved.


14 August 2003

Serveral bugs of DDW-server are fixed: The number of connections is now displayed correctly; the TIME-Function WAIT can be used in SRCP 0.80 mode. The selection of protocols (DCC/NMRA oder MM) has been inactivated due to problems.


06 July 2003

Holger Seider has developed a very nice tool for programming loco decoders in connection with DDW-Server or Linux erddcd. You find it on the download page.
DDW: the TIME functions are available in the new version 0.63.
By starting DDW server an icon in the Windows tray appears. By clicking on this icon with the right mouse button a menu pops up.
In addition, several bugs were corrected due to the reports by Holger Seider and Marcel van Lieshout. Thank you.

Finally, I splitted DDW server und Gplan for download. This reduced file size considerably.


08 April 2003

Serveral bugs of DDW 0.61 corrected (SET M1 and GET POWER were not correctly analyzed)


06 April 2003

The version (0.61) has improved decoder-programing capabilities (thanks to Holger Seider!). The following codes are send back upon programing decoders (like the Linux erddcd): "2" if no programing track is connected; "1" if programing (verify) was successful; and "0" if programierung was not possible, or verify was negative.

Finally, the Linux version of Gplan was updated.


15 March 2003

SRCP-protocol 0.73 and 0.8x is working with the newest DDW-Server version 0.6. It is possible to select the protocol with the settings menu. Socket problems should be reduced, hopefully. All function of SRCP 0.8 protocol should work except the feedbach functions and programming of decoders. However in SRCP 0.73 mode programming of decoders should work!
The Timer component by Roman Lauer has been integrated.
I would like to thank Holger Seider for testing the server and his helpful suggestions. Thank you!

Roman Lauer has updated his components and added a detailed documantation.


23 February 2003

Holger Seider hats written a new version 1.01 of his Railly client. In addition Holger sent me a short manual (in German) about connection of the PC with boosters and feedback modules. You can find it on the german DDW-site.

I completed a new DDW server version (0.53). The problems during repeated connections of the info or feedback channel should be resolved.

For developers of clients SRCP 0.8x a new and improved version of the DDW server is available. The info thread should now terminate. The GA Devices still give no information (GET command and Info modus).

09 February 2003

A small update of DDW-server (version 0.52)


02 February 2003

An alpha-version of the DDW-Servers for the SRCP-protocol 0.8 can be downloaded and tested. It is now possible to select the Protocol version 0.73 or 0.8. Selection of 0.73 causes the DDW-Server to behave like server version 0.51. Developer of clients (SRCP 0.8) should take into consideration that devices are assigned to busses. A listing of the busses and their devices is send during connection of clients. Each device must be initialized before use (protoco version, number of functions, number of speed steps). These data must not be send with the "SET" command. (See examples on the DDL-site of Torsten Vogt ). A short message about errors and problems is appreciated!

A scematic of the home made devices as as replacement for joysticks in connection with Gplan can be obtained from client page.

A new link to the homepage of Michael Geramb who developed a tool for programming TAMS loco decoders can be found on the link page

26 January 2003 Roman Lauer has sent me a new version of his digital direct components. He added two new components: LocoStarge and M6050. Roman still asks to report him your experience with the components.
15 January 2003

small changes on the nmra translation selection

03 January 2003

Several new developments:

1) DDW Server has been updated
it is now possible to control not only turnouts and signals but also locos. However, this function is disabled as long as clients are connected to the server.
b) informations on the connected clients is displayed on the left side in a treeview window.
c) debug mode can be stored permanantly
d) Loco decoders can be programmed e.g. with Gplan and the "Write" command.

2) Gplan has a new feature: According to the demands of my kids the locos can be controlled by two joystick or 2 home made controls. Direction and function can be toggled with the two joystick buttons. A third function (e.g. Telex) can be controlled if both buttons are pressed simultaneously.

3) I switched to C++Builder version 6 for development of the programs.

4) Installation of the programs is hopefully easier than before. Both programs are now available int the "DDW-Suite". However, each program can be installed separately. Unfortunately, the installation file is rather big, about 5 MB.

5) I would like to encourage you to mail any suggestion for improvements or changes. Also, if you experience any problems please drop me a line.


15 December 2002


Roman Lauer has worked on the DigitalDirect component. The serial port should not be blocked anymore after closing the program. Roman asked to further test the components.
01 December 2002

Roman Lauer has developed several components to design servers such as DDW or erddcd easily . Roman asks to test these components extensively and to send him your experience. The components by Roman Lauer and a test server can be found on the Downloadpage

10 November 2002

Holger Seider has written a Client "Raillyplan" with similar features as Gplan. It is worth to try! Holger has added a detailed help. There shouldn't be any problems in operating Railyplan. Raillyplan can be downloaded from the DDW-site. For further information, please contact the autor.


06 November 2002

I worked on the Socket-Thread code, now it should be possible that serveral clients connect to the server simultaneously

A link to a client for the ddw-server was added


12 September 2002

DDW-Server version 0.3 is now available!

Compared to the previous version several features were added:

1) It is possible to connect with more than one client
2) short detection can be activated
3) the "Ga-Manager" from the DDL-erddcd was adapted for DDW
4) DDW-Server can be installed as Service under Windows NT/2000/XP
5) English or German can be chosen as language

Gplan is updated to version 0.4:

1) The Borland database engine is not necessary anymore, the program package became considerably smaller.
) The functions f1 - f4 of the decoders can be programed
3) direct input of SRCP-commands
4) monitoring of info-channel







last changes 01 January 2017