Hardware Support: OpenLCB - Naming
This page discusses how JMRI uses System Names to access OpenLCB-attached resources.
JMRI's Use of Names
JMRI provides an interface to the real layout via internal objects such as Turnouts, Sensors,
etc. that are closely mapped to corresponding physical devices. This mapping is done via
"System Names", which both identify how to access a particular device, and are the key to
looking up the corresponding object in JMRI.
OpenLCB Events
OpenLCB communicates events via messages with a fixed
format: eight bytes of content. We convert this to a 16 hexadecimal digit code with a leading
"x" character, e.g. "x1234567890ABCDEF". We recommend you use upper case for the A-F letters.
You can also enter it with periods separating the bytes: "12.34.56.78.90.AB.CD.EF". In this
case only, one leading zero per byte can be omitted when typing the event; JMRI will insert
them automatically in names. For example, "00.01.02.03.04.05.06.07" can be typed as
"0.1.2.3.4.5.6.7".
OpenLCB Configuration Memory
DecoderPro accesses decoder memory via "CVs". For that purpose, the JMRI OpenLCB provides a
CV syntax that can be used to access OpenLCB node configuration memory:
- CV12345 - A single byte at address 12345 in the default configuration address
space
- CV(252)12345 - A single byte at address 12345 in the 252 address space
- CV12345:4 - Four bytes starting at address 12345 in the default configuration address
space.
- CV(252)12345:4 - Four bytes starting at address 12345 in the 252 address space.
OpenLCB Signal Masts
See the
OpenLCB Signal Mast page for more information on
OpenLCB Signal Mast names.
Back to the main OpenLCB Help page
