LABELS You may use Labels to make connections from one point on a drawing to another point without drawing a line all the way across the drawing. Whether your drawing makes extensive use of labels versus extensive use of lines is a matter of personal choice. The label tool is pointed out below. The lower case "a" is the label tool icon, the upper case "A" is the annotate tool icon.
Upon clicking the label tool, the tool dialog pops up. Type in your label text. The text will appear at the mouse. Move the label around with the mouse.
When the label is over a wire that may be labeled, the "hot spot" is circled. Left-click the mouse to place the label at this point. The label will tool will remain "hot" allowing you to place the same label multiple times, namely at all points to be connected together. You can use the same label text later if you need to add a connection point to the same label. Right-click the mouse or press the Escape key to drop the label tool.
NO CONNECTS and UNUSED PINS You will sometimes have an extra connection on a function block that you do not wish to use. To avoid errors in code generation, you need to indicate that no connection is really your intention. The no-connect tool is the small "X" near the wire tool. The larger "X" near the zoom tool (magnifying glass icon) is the Delete tool.
The no-connect "X" will appear at the mouse. As you move the mouse near a connectable point, it will be highlighted with a circle. Left-click the mouse to place a no-connect here.
It is important to note that ONLY connections defined as "outputs" from a function block can be designated as no-connect. If you wish to leave inputs unused, you must specify a constant value or constant state to be assigned to that input in order to avoid both code generation errors and functional errors in program execution. Function blocks called ZERO and ONE are pre-defined in the library for convenience in assigning values of zero or one to an unused input. Most inputs are active high, therefore ZERO is the most common way to keep the input inactive in the correct manner.
BUSES You can place multiple wires as a group, and these groups are called buses. Use the bus drawing tool group to create buses.
An example of using buses is illustrated below. Use the bus toolbar to create the bus, give the bus a name, and place the bus entry points (angled lines). Use the wire tool to connect function block pins to the bus entry points. Use the label tool (noted above) to assign signal names to each wire connected to the bus. The labels, not the graphic lines, are the deciding factor on what actually gets connected. The bus itself is a graphical element to aid visual recognition of what is connected.
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