GE Industrial Solutions 6KCV300WPD - Manual (Page 30)

5.4 Editing the of Blocks
Section 5.2 above explained that the ports of blocks represent input and output variables of the underlying
piece of code and that these ports can be connected together. Drawing a connection line is the most common
operation on the ports of blocks. Other operations are available by opening the ports dialog.
5.4.1 Opening the Ports Editor Dialog
The ports dialog for a block is opened by double-clicking a block or by selecting a block, pressing the right
mouse button to open the context sensitive menu and selecting
Ports.. from this menu. The ports dialog is
used for changing properties of all ports of one block
Figure 5.4.1.1: Ports Editor Dialog
Within the Ports Editor dialog there are two lists that include all input and output ports. After selecting one of
the ports its properties can be changed by the control elements in the middle of the dialog window. The port
that is selected immediately after opening this dialog is determined by the mouse position at the time the
block was double-clicked or the right mouse button was pressed. Thus the user can determine the initial
selection by double-clicking a port of the block.
5 . 4 2 Setting the Connection
For each port the type of connection can be changed by selecting an item of the drop down list box. The
following selections are available:
None: the port has no connections. Output ports can be left open (if the result is not used). Input ports
have always to be connected to something.
Variable: a variable is used for connecting the schematic to the embedding program of the target system.
Variables are described in detail in Chapter 6.
Tag: a tag is a connection that is done by setting the same tag on different ports within one schematic.
Tags are useful for connections to many ports. All ports that share the same tag string are connected.
Connection line: this choice is selected if a connection line was drawn. Setting the combo box to this
value will cause an error after closing the dialog.
Constant: the input of a block will be set to a constant value. Setting an output port to a constant will
cause an error message after closing this dialog.
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