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DCC Working Group Active Topics

NMRA DCC Working Group Active Topics

Lists of inactive and completed topics are also maintained.

This page was most recently update on January 15, 2005 to add a new entry for Topic 0501151 - Additional Functions.

Other recent changes include:

Topic 9910241 - Analog Output Instruction

Soundtraxx has proposed using a reserved packet format for analog output.

Work-in-progress drafts and background information will be posted periodically. (Updated July 9, 2004)

Brian Barnt is coordinating this topic.

Topic 0304231 - Additional Mfg CVs for Accessory Decoders

David Nickolson of ZTC has proposed adding CVs 542-544 to the Manufacturer Unique area starting at CV 545.

There has been a general consensus to accept this proposal. David will be asked to revive the effort.

Work-in-progress drafts and background information will be posted periodically. (Updated Jul 9, 2004)

Topic 0305001 - Medium Plug Enhancement

Several manufacturers, including Roco and S-Helper Service, have been working on expanding the medium connector to support more functions. Several different options for standardization have been discussed.

Reinhard Mueller will try to coordinate discussion among the manufacturers. Work-in-progress drafts and background information will be posted periodically. (Updated July 27, 2004)

Topic 0305051 - Decoder Lock Proposal

AJ Ireland of Digitrax is proposing a new method of programming multiple decoders in a single locomotive.

Bob Jacobsen is coordinating discussion on this topic. Work-in-progress drafts and background information will be posted periodically.

Topic 0307121 - New Decoder Register Matrix

Rutger Friberg has proposed changing the way CVs are accessed and organized.

Reinhard Mueller will coordinate discussion.

Work-in-progress drafts and background information will be posted periodically.

September 2, 2004: This is a difficult topic, as several manufacturers have already started building products in non-standard ways.

Topic 0307122 - Service Mode Decoder Lock Proposal

Bernd Lenz, on behalf of a new manufacturer, is proposing an additional Service Mode instruction to prevent the programming of decoders in low-end systems where there is no programming track.  Using this method would eliminate the problem of re-programming every decoder on the layout to the same address. This proposal also eliminates a conflict between RP-9.2.1 and RP-9.2.3.

This topic was updated on September 6, 2004; a draft has been made available.

Bob Jacobsen is coordinating this topic. Work-in-progress drafts and background information will be posted periodically.

Topic 0307163 - Glossary

A proposal was received to convert the Draft Glossary document to a Technical Note.

Work-in-progress drafts and background information will be posted periodically. There is currently a glossary version there for comments. (July 21, 2004)

Topic 0307165 - Clarification / Rewording of RP-9.2.1 and RP-9.2.2

This topic refers to poor wording in a particular section of RP-9.2.1 and RP-9.2.2, and a possible conflict with the eventual RP-9.3.1 and RP-9.3.2. The working must be made consistent with what was agreed to in the initial discussions.

Bob Jacobsen is coordinating this topic. Work-in-progress drafts and background information will be posted periodically.

Topic 0309301 - RP-9.3.1 Revision

Extensive changes in the bidirectional communications have been proposed for RP-9.3.1. This includes changing the electical specifications, baud rate, and timing of communications.

Bob Jacobsen is coordinating this topic. Work-in-progress drafts and background information will be posted periodically.

Topic 0309302 - RP-9.3.2 Revision

In concert with the changes to RP-9.3.1 proposed in topic 0309301, this topic proposes changes to the details of the messages communicated.

Bob Jacobsen is coordinating this topic. Work-in-progress drafts and background information will be posted periodically.

Topic 0405221 - Streaming Mode Programming

The Working Group is discussing possible protocols for loading data into a decoder via a streaming-mode protocol. The goal is to allow loading large volumes of data to a decoder over the rails without having to remove the decoder from the engine. This can be useful in upgrading the decoder's firmware, loading sound data etc. This topic was created on May 22, 2004 after initial discussions within the Working Group.

Gil Fuchs is coordinating this topic. Development of a working prototype and asssociated documents for this topic is expected to take six months. Work-in-progress drafts and background information will be posted periodically.

On September 6, 2004, drafts of the protocol specification and background note were posted for comment.

Topic 0408251 - In-rush Current Compatibility

Modelers have reported incompatibilities between certain locomotives, decoders and command stations / boosters during the initial current draw. Related problems have been observed both in normal operation and when service mode programming. Members of the Working Group feel that this would be a good thing to coordinate among the manufacturers of locomotives, decoders, boosters, circuit breakers and others components. Discussions within the working group have started.

This topic was created on August 25, 2004 after initial discussions within the Working Group.

Mark Gurries is coordinating this topic.

Topic 0409061 - Asymmetric DCC signal

There are places on a model railroad where localized information needs to be transferred to a locomotive, e.g. e.g. to stop a train automatically at a certain place. This topic is an attempt to develop a common specification for doing via an asymmetric DCC signal. This is a signal where the positive-going part of the waveform has a different amplitude from the negative going part. A decoder can detect this difference and act on it.

This is intended to be an optional capability that can be implemented cheaply, and independently of the command station.

Reinhard Mueller will coordinate this topic. As there are already implementations on the market, with more expected, this topic should move quickly. This topic was crated on September 6, 2004.

Work-in-progress drafts and background information will be posted periodically. A draft has been posted.

Topic 0409121 - Improved Wiring of the Small Connector

This topic describes a recommended way of wiring the small connector so that lamps continue to work in DC mode in both directions. This wiring also provides a symmetric load.

The intention is to put this recommended wiring into an appendix of RP 9.1.1 so that manufacturers will know about it, and may use it or not without affecting the conformance of their product.

Reinhard Mueller will coordinate this topic. As this is a recommendation, not a requirement, this topic should move quickly. This topic was created on September 12, 2004.

A draft was posted on September 20, 2004.

Topic 0501151 - Additional Functions

Discussion is taking place on how to support additional functions (e.g. lights, sounds, etc) beyond the F0 through F12 defined now.

Reinhard Mueller will coordinate this topic.