One of the advantages of the Märklin-Digital-System is that it is relatively simple to build most
of the components yourself. Owing to the quite large number of users (in Germany), a lot of electronics engineers, technicians and hobbyists have put their know-how to use in this area. This have resulted
in several conversion tips-and-tricks for the commercial products, as well as a lot of DIY instructions
for all sorts of Decoders, feedback modules, controlunits, Boosters etc. Only loco decoders haven't been included in any of these sources.
One reason for this is that the IC MC145029 used in Electors EDITS article series was obsoleted in the late 80's, another reason is that the functionality found in the commercial decoders of today can only be achieved by using special IC's, or microcontrollers programmed for this particular purpose.
But now that have changed. After a long time in development, the two danes
(H.C. ěrstedsvej 56, 2.tv, DK1879 Frederiksberg C, Denmark, email@example.com) and Frankie Frederiksson (Dyndevej 20, DK3721 ěstermarie, Denmark, firstname.lastname@example.org)
have completed their featurepacked loco decoder design, called the "wikinger decoder" because of the
country of origin.
I am pleased to present the versions for AC-Motor and for DC-motor of this very versatile decoder, which compares favourably to most commercial decoders.
The design described is the decoder without speed control, for the conventional Märklin
universal motor (AC-decoder). I have described it in MIBA Spezial Nr.42 (1999) S.60). Der the version for for DC motors is finished also and the description will follow in one of the next MIBA-issues. Circuit-diagram and layout are also available.
Decoders with load-dependant speed regulation are likely to appear in the future, and not only for DC-motors (which isn't very special), but also for the universal motor.
The decoder is for digital systems only, and especially for the Märklin-Digitalsystem. All parameters are set (programmed) from the central unit, while the loco is placed on the track. The PIC microcontroller on the decoder board can even be programmed or updated without removing it from the loco. A short summary of the features of the Wikinger decoder:
Those who do not want to buy an already programmed PIC, can perform the
programming themselves. To do this you will need a PC, some software and
some hardware. I use PIP02 programming software and a simple 16F84-programming
hardware from Jens Dyekjaer Madsen, as well as his special driver JDM84.
All three items are available on Madsens
Earlier I tried using the well known LUDOPIPO programmer and the COM84 driver, but found that this even simpler hardware could not program the PIC in-circuit reliable. This may be related to the fact that the PC used was a laptop model (the output voltage from a laptop serial port is usually lower than that from a desktop PC), but the simple 16F84-programmer by Jens Dyekjaer Madsen shows no such problems, and can even be implemented inside the serial port connector shell.
Building the programer incl. pcb-layou and the programming of the PIC I have describe in MIBA Digital Nr.1 (2000) S.74, too.
Interested? Of course. But please be patient - the appearance of this article in MIBA Digital Spezial and it┤s continuing in one of the next issues have priority.
Thus: In the meantime, have a look at the webpages from Bo Brændstrup and Frankie Frederiksson, and come back here in a couple of weeks.
Because of certain reason Bo BrŠndstrup┤s Homepage is not available every time you can download the newest official version of the Wikinger-program here. It┤s development is in progress.
This translation was made by Bo Brændstrup from Denmark (one of the Wikingers ;-)). Many thanks to him for this grateful work. Any linguistic errors you may encounter is due to me trying to correct small misunderstandings.
© 1999 by Bo Brændstrup | H.C. Oerstedsvej 56, 2.tv. | DK-1879 Frederiksberg C / Denmark | email@example.com