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Table of Contents
CAN-GCA Overview
CAN
GCA CBUS supports a small subset of the CBUS protocol.
CBUS protocol documents are a copyright of Mike Bolton and Gil Fuchs
Professional boards & kits
Only Kits bought from CANBUS - A universal layout control system
CAN-GCA module firmware is based on CAN using the industrial CAN Bus.
Example Network
Bus termination
The very high noise immunity is achieved by ensuring that the differential impedance of the bus is maintained at a very low level using low value resistors (120 ohms) mounted at each end of the bus.
| On all CAN-GC boards this termination resistor is already mounted and can be activated by setting a jumper. |
Connection cable
The best suitable cable for connection between all CAN-GCx modules is CAT-5 cable, mostly known as CAT-5 Patchkabel cable.
Almost any computershop or DIY Market sells this cable for pretty low prices. (e.g. Reichelt 4X2 AWG26/7-10)
| DB9 Pin | Function | CAT-5 color | Remark |
|---|---|---|---|
| 1 | GND | brown/white | |
| 6 | GND | green/white | mandatory¹ |
| 2 | DCC- | orange/white | Booster |
| 7 | CANL | blue/white | mandatory¹ |
| 3 | LN or +12V | green | |
| 8 | CANH | blue | mandatory¹ |
| 4 | DCC+ | orange | Booster |
| 9 | Not used | ||
| 5 | +12V | brown | mandatory¹ |
¹) Minimal cable configuration.
Pin 2 and 4 are only needed when ORD-3 booster is used in the same system.
Changing wire colours could cause errors.
Links
Reichelt Elektronik
Alternative cable
| For testing and small layouts. |
Standard full wired male to female extension RS232 cables are allowed, but up to a certain limit. (e.g.: Reichelt AK2300)
It is never experienced how many can be used. A few will not disturb the communication, but it is not able to conduct the full 3 Amp of the CAN-GC1(e).