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Layout Command Control® (LCC)

Layout Command Control

 

Model railroaders expect a lot from the electronics on their layouts. They want to automate accessories, simplify operation of their staging yards, have fine control over layout lighting, and build realistic dispatcher panels. Home and club layouts are getting more detailed and complicated, and existing electronics for control systems are having a hard time keeping up.

Layout Command Control Development

The process of developing networks and protocols for layout control are not trivial.  No small group of individuals are able to fully develop the necessary code, protocols and the like to sucessfully impliment the concept of having complete, integrated control of a layout, be it a simple 4 by 8 foot sheet of plywood to a large complex, multi-deck masterpiece.  Using the current open source development process, a group named OpenLCB has stepped up to take on this task.  You can find the details of their work, process, organization and even how to participate on their development process at their website located at:  https://openlcb.org/.  OpenLCB is developing the Standards and providing Technical Notes to support those Standards that will be used in the development of hardware to control a layout.

Memorandum of Understanding

The NMRA and OpenLCB have entered a Memorandum of Understanding that provides the details of the relationship between the two organizations and states the responsibilities for each oraganization.

View the Memorandum of Understanding (MOU)

Standards

The NMRA, in its standards and recommended practices, addresses only the specific standards and recommended practices for model railroads.  These standards and recommended practices do not address any legal requirements.  It is the responsibility of the manufacturer to determine if their product conforms to all applicable governmental laws and regulations.

The Standards for LCC® are organized so that each Standard has a corresponding Technical Note.  The Technical Notes provide additional information and reasoning about what was and was not included in the Standard.  These Standards, developed by OpenLCB, are submitted to the NMRA for review and comment by the membership.  Once the reviews are complete, the NMRA Board of Directors adopts the Standards as the official NMRA Standard for Layout Command Control.

Layout Command Control Standards

 
Standard Tech Note Test Procedure NMRA Status
  TN-9.7.0.1 Glossary    
  TN-9.7.0.2 Common Information    
S-9.7.0.3 Unique Identifiers TN-9.7.0.3 Unique Identifiers   Adopted 24-Jan-25
S-9.7.0.4 Event Identifiers TN-9.7.0.4 Event Identifiers   Adopted 24-Jan-25
PHYSICAL LAYER      
S-9.7.1.1 CAN Physical TN-9.7.1.1 CAN Physical   Adopted 24-Jan-25
DATA LINK LAYER      
S-9.7.2.1 CAN Frame Transfer TN-9.7.2.1 CAN Frame Transfer   Adopted 24-Jan-25
NETWORK & TRANSPORT LAYER      
S-9.7.3 Message Network (CAN + TCP/IP) TN-9.7.3 Message Network (CAN + TCP/IP)   Adopted 24-Jan-25
S-9.7.3.1 Event Transport TN-9.7.3.1 Event Transport   Adopted 24-Jan-25
S-9.7.3.2 Datagram Transport TN-9.7.3.2 Datagram Transport   Adopted 24-Jan-25
SESSION LAYER      
S-9.7.4.1 Configuration Description Information TN-9.7.4.1 Configuration Description Information   AAdopted 24-Jan-25
S-9.7.4.2 Memory Configuration TN-9.7.4.2 Memory Configuration   Adopted 24-Jan-25
S-9.7.4.3 Simple Node Information TN-9.7.4.3 Simple Node Information   Adopted 24-Jan-25
S-9.7.4.4 Firmware Upgrade TN-9.7.4.4 Firmware Upgrade   Adopted 24-Jan-25
S-9.7.4.5 Broadcast Time Protocol TN-9.7.4.5 Broadcast Time Protocol   Adopted 24-Jan-25
S-9.7.4.6 Train Control Protocol TN-9.7.4.6 Train Control Protocol  
Adopted 24-Jan-25
S-9.7.4.7 Train Search Protocol TN-9.7.4.7 Train Search Protocol   Adopted 24-Jan-25
S-9.7.4.8 Function Description Information TN-9.7.4.8 Function Description Information    Adopted 24-Jan-25
       
STANDARDS UNDER REVIEW      
see Documents Under Revision page      

Frequently Asked Questions About Layout Commmand Control

LCC FAQs

Videos

Introduction to Layout Command Control® (LCC)

Updated 23-Oct-24 commeents/corrections: tech-elec [at] nmra.org (subject: nmra.org%3A%20Layout%20Command%20Control%20Page)