PLC Programming

Visualizing a Traffic Signal Unit...
3.2 Visualizing a Traffic Signal Unit...
With the visualization of CoDeSys you can quickly and easily bring project variables to life. We will
now plot two traffic signals and an ON-Switch for our traffic light unit which will illustrate the switching
process.
Creating a new visualization
In order to create a visualization you must first select the range of Visualization in the Object
Organizer. First click on the lower edge of the window on the left side with the POU on the register
card with this symbol and the name Visualization. If you now choose the command 'Project'
'Object Add', then a dialog box opens.
Enter here any name. When you confirm the dialog with OK, then a window opens in which you can
set up your new visualization.
Insert element in Visualization
For our TRAFFICSIGNAL visualization you should proceed as follows:
Give the command 'Insert' 'Ellipse'.Insert..Ellipse.>Proc and try to draw a medium sized circle (2cm).
For this click in the editor field and draw with pressed left mouse button the circle in its length.
Now doubleclick the circle. The dialog box for editing visualization elements opens
Choose the category Variables and in the field Change color enter the variable name .L1_red or
"L1_red". That means that the global variable L1_red will cause the color change as soon as it is set
to TRUE. The dot before the variable name indicates that it is a global variable, but it is not
mandatory.
Then choose the category Color and click on the button Inside in the area Color. Choose as neutral
a color as possible, such as black.
Now click on the button within in the area Alarm color and choose the red which comes closest to
that of a red light.
3-12 CoDeSys V2.3