2.2. Configuration

Cascade Historian™ : Version 6.4
	Chapter 2. Using the Cascade Historian

The Cascade Historian is normally used with a configuration file called, for example, hi.cfg.

A configuration file is useful for sending initial start-up commands or specifying global defaults. These would include, for example:

`history`	creates a new history.
`bufsize`	sets the history buffer size.
`deadband`	sets the history value deadband.
`filebase`	associates the history with a file for data storage.
`register`	registers histories with the Cascade DataHub.
`unregister`	unregisters histories with the Cascade DataHub.

The syntax for configuration commands is based on Lisp syntax. It consists of the name of the command, followed by a space-separated list of arguments, all enclosed in parentheses, like this:

(command arg₁ arg₂ arg₃ ...)

These commands are commonly written one per line for clarity, but it is not necessary to do so. Any number of commands can be written on a line, each enclosed by parentheses. Also, if a command becomes very long, it is possible to break it up into several shorter lines with line breaks to make the configuration file more readable. In either case, the parentheses are what delimit the command.