FREMO Interlocking

FStw: FREMO Stellwerk (FREMO interlocking;-)

The FStw will not be a monolithic interlocking in a big box with the outdoor equipment (turnouts, signals,...) mounted to it with thick cabling. Instead it will be a decentralized approach, where element controller (EC) are communicating on a bus, the LotusNet. Also the user interface (UI) will be connected by such EC, no matter which type it is, the only exception may be a UI on a PC, which will be directly communicating via LotusNet. Even the communication to our FREMO Block will be done by Lotusnet.
The FStw will be a pure control table interlocking system. This will give the chance to build up interlockings for different country logics, not only the german EBO (EisenbahnBetriesOrdnung;-).

Why a decentralized concept?
This will give us the necessary flexibility, to control a wide range of stations from a "AWANST (Ausweichanschlußstelle)" with two turnouts an no signal up to big stations with a lot of turnouts, signals, and so on. Additionally it makes the development of the necessary subsystems much more easy.

Common information

In this chapter we will collect some information for common use, eg projects with the FStw.

Documentation for developers

The whole developer documentation will be written in english language. This will be the contribute to the "E" in FREMO and to all the other people, who are interested in our project.

General items

All those items, which are common to the whole interlocking, will be collected here, eg system architecture, background information ...


The documentation for the subsystems, eg EC(ElementController), CC(CommunicationController), CU (Central Unit, Zentralrechner)....

How to build developer documentation

User documentation

If in the future, there will be some user documentation, it should be at least in english and german language. Hopefully there will be enough volunteers for the translation.