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Hardware Support: MERG CBUS - Connection Details

This page describes technical details of JMRI's MERG CBUS connection support.

CAN Adapters

JMRI MERG Connections

JMRI's general approach is to support as many hardware combinations as possible. By supporting as many people and their hardware desires as possible, we can create a growing community of developers, hence more code.
As part of this, the JMRI CAN support is designed to use as many CAN adapter types as possible.
Not many PCs have a RS232 serial port now, however is still supported.

Where USB interfaces are used, the Baud rate is irrelevant.

MERG CBUS CAN Network ID

All MERG CBUS modules need a CAN ID, and JMRI is no exception.

Modules must not have a duplicate CAN ID

The CAN ID is separate to any NODE ID's used in MERG CBUS Long Events.

Node numbers are for MERG CBUS long events, CAN ID's are purely for the CAN protocol transmission and are largely irrelevant in JMRI processing MERG CBUS events.

Most MERG modules can do "enumeration" for MERG CBUS, but some other adapters can't because of their intrinsic latency. Their slow replies effectively make them invisible.
Therefore Mike Bolton, one of the MERG CBUS developers suggested that JMRI use a CAN ID of 126. That's a fixed value in some systems.

If you have multiple copies of JMRI attached to a MERGCBUS network, be sure to give these unique CAN ID's.

CAN via MERG CAN-RS or CAN-USB

JMRI MERG Connection canrd canusb canusb4 adapter

A CANUSB4 should not normally require special drivers to be installed, it should just work.

If using a MacBook Pro running Mojave and are struggling with drivers for a CANUSB / CANUSB2, the appropriate driver is available from FDTI for the UM245R, the VCP option.
( Tip courtesy of John (G8GKU) via JMRI Users at Groups.io )

Default setting shown on right hand side after the " : "

Serial Port - Select the serial or USB port that your CAN interface is plugged in to.

Connection Prefix : "M"

Connection Name : "MERG"

Additional Connection Settings shown when box checked

Baud Rate Select

CAN ID for CAN-USB : 126 ( selectable from 120-127 )

Connection Protocol : "MERG CBUS" ( "OpenLCB", "Raw CAN" and "Test - do not use" also selectable )

CAN via MERG Network Interface

JMRI MERG Connection network interface

Methods using this option include :

IP Address / Host Name : ( none ) - enter an IP address for fully manual configuration.
Optional hostname for ZeroConf / mDNS configuration does NOT currently work, use IP or localhost.
"localhost" can be used on most systems if the CAN server is running on the same machine.

TCP / UDP Port : 5550 - Port address setting of the TCP connection

Connection Protocol : "MERG CBUS" ( "OpenLCB", "Raw CAN" and "Test - do not use" also selectable )

Connection Prefix : "M"

Connection Name : "MERG"

Additional Connection Settings shown when box checked

CAN ID for CAN-USB : 126 ( selectable from 120-127 )

Gateway : Pass All ( Filtering also selectable )

CAN via GridConnect adapter

JMRI MERG GridConnect Adapter

Serial Port - Select the serial or USB port that your CAN interface is plugged in to.

Connection Prefix : "M"

Connection Name : "MERG"

Additional Connection Settings shown when box checked

Baud Rate Select

Connection Protocol : "MERG CBUS" ( "OpenLCB", "Raw CAN" and "Test - do not use" also selectable )

CAN via GridConnect Network Interface

JMRI MERG GridConnect Network Interface

IP Address / Host Name : ( none ) - enter an IP address for fully manual configuration. Optional hostname for ZeroConf / mDNS configuration.

TCP / UDP Port : 0 - Port address setting of the TCP connection

Connection Protocol : "MERG CBUS" ( "OpenLCB", "Raw CAN" and "Test - do not use" also selectable )

Connection Prefix : "M"

Connection Name : "MERG"

Additional Connection Settings shown when box checked

Gateway : Pass All ( Filtering also selectable )

CAN via Lawicell CANUSB

JMRI MERG Lawicell USB Connection

Serial Port - Select the serial or USB port that your CAN interface is plugged in to.

Connection Prefix : "M"

Connection Name : "MERG"

Additional Connection Settings shown when box checked

Baud Rate Select

Connection Protocol : "MERG CBUS" ( "OpenLCB", "Raw CAN" and "Test - do not use" also selectable )

CAN Simulation

JMRI MERG CAN Simulation Connection

A simulated Command Station is started for this connection, see CBUS Simulation Tools.

Defaults to CAN ID 120

Serial port : ( none )

Connection Prefix : "M"

Connection Name : "MERG"

Additional Connection Settings shown when box checked

Baud Rate : None ( grayed out dropdown unselectable )

Connection Protocol : "MERG CBUS" ( "OpenLCB", "Raw CAN" and "Test - do not use" also selectable )

Direct Serial Connection

JMRI MERG Direct Serial Connection RfID

Serial Port Select- Choose the serial or USB port that your CAN interface is plugged in to.

Concentrator range Select : "A-H" , unselectable in grayed out select box

Device Type Select : "MOD-RFID125", unselectable in grayed out select box

Adapter Select : Generic Stand-alone ( MERG Concentrator alternate option, choosing this allows the Concentrator Range select, with an additional "I-P" option )

Protocol Select : CORE-ID
Alternate option - Olimex, enables a device type of MOD-RFID1356MIFARE in the device type dropdown.
Alternate option - Parallax
Alternate option - SeeedStudio
Alternate option - EM-18

Connection Prefix : "F"

Connection Name : Rfid

Additional Connection Settings shown when box checked

Baud rate Select : automatic ( unselectable, grayed out select box )

JMRI Help

Main JMRI MERG CBUS Support page

JMRI's general CAN support

JMRI RFID Support

MERG CBUS 3rd Party Links See link for the MERG CBUS Developers Guide