Introduction

DCC is a communication standard for model railways. It is mostly specified by the NMRA, and is written as a bunch of standards and recommended practices. Unfortunately, the specifications are quite tedious to read, and newer parts of the standards (including the RailCom specification) seem to be partially translated from German, with some mistakes here and there.

Decoders

Within DCC, there is a distinction between two types of decoders:

• Mobile decoders (like locomotives, wagons, etc)
• Stationary decoders (like switches, signals etc)

If the RailCom extension of the DCC specification is NOT implemented, it is a one-way communication method.

Important

Even with RailCom, DCC is not particularly suited for detectors. This is mostly due to the method of 'you shall not speak unless spoken to', which is a problem on bigger layouts. Because of this, a lot of manufacturers also have means of connecting a base-station to decoders through other means.