JMRI: Logix Table Help

The Logix Table

A Logix is a small group of Conditionals focused on a single task on the layout. Each Conditional may be viewed as a statement of the form:

if (logical expression) then (action). The "logical expression" part of a Conditional tests the state of a group of user-specified conditions on the layout, for example, whether certain turnouts are closed or thrown, or whether a block is occupied. The "action" part of the Conditional specifies what action is to be taken if the state of the logical expression changes.

The Logix Table lists all currently defined Logixs by their system name and user name. The last column of the table provides an easy way to edit a Logix and its Conditionals. Simply clicking the Edit button for a Logix, will bring up the Edit Logix window. The Edit Logix window also provides for deleting a Logix.

The Enabled column allows you to enable (checked) or disable (unchecked) a Logix. A Logix does not have a state as many JMRI entities do. A Logix does have the capability of being "enabled" or "disabled". When a Logix is not enabled, the logical expressions of its Conditionals are still evaluated, but the actions specified in the Conditionals are not taken. When a Logix is enabled after having been disabled, its Conditionals are recalculated and appropriate actions taken.

To create a new Logix, click the Add button at the bottom of the Logix Table. This will bring up a Create Logix window. Entering a system name and a user name, then clicking Create Logix, will create the Logix, and bring up the Edit Logix window. Once a Logix is created, its system name cannot be changed. Its user name, however, may be changed in either the Logix Table or the Edit Logix window. A new user name may be any useful text, provided the new user name was not previously assigned to another Logix.

The File menu at the top of the Logix Table provides for printing this table and for storing the Logixs and their Conditionals in a layout configuration file. Selecting either store option will bring up a dialog for naming a configuration file for writing Logix information and all other configuration information (e.g., sensors, lights, turnouts, signal heads, routes etc.). If you are updating an existing file, simply click its name, and it will be copied into the name entry.

For more information, consult the Logix documentation on the JMRI web page http://jmri.sourceforge.net/ .