Wired Node-to-Node Planning Guide

Table of contents

Wired Node-to-Node Planning Guide
1. Introduction
2. References

Introduction

In the LCC Fusion Project, reliable wired communication between nodes is achieved using the CAN Bus standard. CAN (Controller Area Network) provides robust, differential signaling that is ideal for noisy environments and long cable runs.

In addition to wireless options such as Wi-Fi and ESP-NOW (which are optional and not required to understand this guide), LCC Fusion supports wired node-to-node connections using a wired CAN Bus.

Configuring Wired Node-to-Node Communication

Identify the Bus Ends
- CAN requires a linear bus with two ends.
- Termination resistors (120 Ω across CAN_H and CAN_L) must only be present at the two endpoints.
In the LCC Fusion Project:
- The Node Card, Quad-Node Card, and Node Bus Hub all include automatic termination circuits.
  
  Automatic CAN termination applies when using LCC Fusion hardware exclusively; manual termination is only required when integrating non-Fusion CAN devices at the ends of the bus.
- Termination is engaged only when the device is physically at the end of the bus.
- No jumpers, switches, or manual configuration are required.
When sharing the CAN Bus with other LCC devices (non-Fusion):
- External devices generally do not provide automatic termination.
- If such a device is at the end of the bus, its termination must be enabled manually or added with an external resistor.
- Across the entire network—Fusion and non-Fusion combined—there must always be exactly two terminations, one at each end of the bus.
Select Cabling
- Within the LCC Fusion Project, the CAN Bus is carried using standard network cables (CAT5 or CAT6).
- Standard network cables are used only as convenient twisted-pair wiring; Ethernet signaling or networking concepts do not apply.
- These cables provide twisted pairs, which are ideal for differential signaling (CAN_H and CAN_L).
- Using network cables ensures consistency, easy availability, and compatibility with Node Cards and Node Bus Hubs.

Chain Hubs if Needed

Multiple LCC Fusion Project Node Bus Hubs (PCB boards) can be interconnected to expand the system.
Each hub provides both multiple 8-pin headers (for direct board-to-board connections) and a pair of RJ45 sockets (for remote connections using standard CAT5/6 network cables).
Node Bus Hubs may be chained together as a planning option when layouts expand beyond a single physical hub.
This flexibility allows hubs to be chained together locally or over longer distances while maintaining proper signal integrity on the CAN backbone.
Automatic termination still ensures that only the physical endpoints of the combined chain are terminated.

The diagram below is a conceptual illustration of CAN topology and hub relationships; it is not intended to represent exact wiring or physical placement.

flowchart LR; 
nonFusionNode["Non-LCC Fusion<br>Node/Device<br>(CAN Bus Termination)"]
can(("CAN Bus"));
hub[["LCC Fusion<br>Node Bus Hub"]];
hub2[["LCC Fusion<br>Node Bus Hub"]];
n1[["LCC Fusion<br>Node Card<br>(CAN Bus Auto-termination)"]];
n2[["LCC Fusion<br>Node Card<br>(CAN Bus Auto-termination)"]];
pc[["LCC Fusion<br>Power-CAN Card"]];
iocards[["LCC Fusion<br>I/O Cards"]];
iocards2[["LCC Fusion<br>I/O Cards"]];
bb1[["LCC Fusion<br>Breakout Boards"]];
bb2[["LCC Fusion<br>Breakout Boards"]];
   
subgraph layout ["Train Layout"];
direction LR;
nonFusionNode --> can;
can --> n1;
can --> pc;
subgraph Installation ["LCC Fusion<br>Installation"]
n1 <--> |"CAN"|hub;
pc --> hub;
hub <--> |"CAN"|hub2;
hub --> |"Network Cable, or <br/> Direct Connection"| hub2;
hub --> iocards;
hub2 --> iocards2;
n2 <--> |"CAN"|hub2;
end;
iocards <--> bb1 <--> devices((Devices));
iocards2 <--> bb2 <--> devices2((Devices));
end;
   
classDef lSalmonStyle fill:#FFA07A,stroke:#333,stroke-width:2px,font-size:24px;
class hub,hub2 lSalmonStyle;
classDef lightGrayStyle fill:#d3d3d3,stroke:#333,stroke-width:2px,font-size:24px;
class layout lightGrayStyle;

Common Planning Notes

CAN uses electrical bus wiring, not Ethernet networking.
Automatic termination is handled by LCC Fusion hardware when used exclusively.
Manual termination is only required when integrating non-Fusion CAN devices.
Multiple Node Bus Hubs may be chained together to extend the bus.

For general questions about CAN wiring and behavior, see the main FAQ.

Benefits of Wired CAN in LCC Fusion

Reliable – CAN is robust against electrical noise and long distances.
Modular – Node Bus Hubs allow plug-and-play expansion.
Error-Proof – Automatic termination prevents configuration mistakes.
Scalable – Multiple hubs and nodes can be chained together as one continuous bus.

Wired Node-to-Node Planning Guide

Introduction

Configuring Wired Node-to-Node Communication

Common Planning Notes

Benefits of Wired CAN in LCC Fusion

References