If And The Boolean Expressions; Boolean Expressions - AMX AXCESS CONTROL SYSTEM PROGRAM Instruction Manual

IF and the Boolean Expressions

IF and the Boolean Expressions
While your first program may seem complicated, it doesn't show the real power of the Axcess
language. At this point, the program is button-for-button. This means that each button has only one
function, with no special conditions or considerations. The control panel has a separate section of
buttons for each piece of equipment.
In many cases, you may want the same number of functions with fewer buttons. A common
solution is to have several groups of buttons with similar functions reduced to one group, with a set
of buttons that selects which piece of equipment the buttons control. You could set one button for
each piece of equipment to select a camera, and one set of camera control buttons. Your panel could
now look like the one in FIG. 19.
FIG. 19 Revised Touch Panel layout for your program.
This configuration has seven fewer buttons than before. In this configuration, the user selects the
camera with the Select button, then controls it with the camera control buttons. This will not be a
button-for-button program because the camera control buttons have three possible functions each.
In the program, you will use Boolean expressions to select the correct function of the camera
control buttons.

Boolean Expressions

A Boolean, or relational expression, is used to tell Axcess whether or not to execute a particular
function or functions in the program. When your program tells Axcess to branch off in a different
direction, the program can either continue the way it is going, or it can jump to a different section of
the program. In this case, Axcess must use a Boolean expression to judge certain conditions before
continuing.
Axcess Programming Language 63