7.5 Connecting Instances in your SmartDesign

In a SmartDesign, pins and ports are connected by nets. You can create manual connections between pins of the instances and ports in your design using the canvas.

Unused input scalar pins and output ports are set to high (1) or low (0). Unused input bus pins and output ports are set to a constant. Unused output pins and input ports are left unconnected when marked as unused.

Important: The nets that connect PAD pins and ports are called PAD nets. Such PAD nets cannot be deleted.

For more information one pins and ports, see .7.4 Creating Pins and Ports for Connecting Instances in the SmartDesign

To connect instances in your design, use either of the following methods.

7.5.1 Method 1: Using the Drag and Drop Feature

Hovering your cursor over a pin or port activates the connection mode automatically and the cursor changes to a crosshair. Click and drag the mouse pointer to the target pin or port and release the mouse button to make the connection.

  • For pins, the connection mode activates when you hover over a pin icon or a pin name.
  • For nets, the connections mode activates when you hover over any part of the net.
  • The connection mode does not activate when you hover over pins, ports, or nets in the following cases:
    • When in a hierarchical view
    • When Zoom to Selected Area mode is activated
    • When Add Note mode is activated
    • When the canvas is in a read-only Filtered mode

7.5.2 Method 2: Using the Right-click Menu

You can also connect multiple pins or ports through the right-click menu options.

To connect the selected pins, perform the following steps:

  1. Select a pin
  2. Press the Ctrl key and select the required pins
  3. Right-click on any of the selected pins and click Connect
Note: The Connect menu option is enabled only if the connection operation between the selected pins is logically feasible.

7.5.3 Showing or Hiding Nets and Net Names

You can choose to show or hide nets and net names on the canvas.

To show or hide nets, click Show or Hide Net toggle icon in the SmartDesign toolbar. When a net is hidden, the net stubs that the hidden net is connected to are still visible. Selecting the net stubs shows the RATS net connection of the net.

To show or hide net names, click Show or Hide Net Names toggle icon in the SmartDesign toolbar. The net names are displayed alongside the net. Hiding net names makes the canvas less cluttered for big designs.

Tip: Net names always display in a tooltip when the cursor is hovered over the net.

7.5.4 Performing Operations on Nets

When a net or multiple nets are selected, the following commands are available in the right-click menu.

Operation Action
Connect The Connect command combines all the selected pins or ports to form a connection. Selecting a net is functionally equivalent to selecting all pins and ports that this net is connected to. Therefore, if you connect a net and a pin, it is equivalent to connecting all pins/ports of the net and the newly selected pin/port. The Connect command can also be used to connect a net to another net if one of the nets is not driven.
Go to Driver When a net is selected, the Go to Driver command centers the view on the net’s driver pin or port, zooms away, and selects the net driver. Go to Driver traces the net to the driver at the local level of hierarchy. It does not traverse hierarchy. The Go to Driver command is not available when multiple nets are selected, or the selected net has no driver. In the latter case, the net displays as a dotted line.
Highlight The Highlight command highlights all the selected nets with the picked color. If any design objects are already highlighted, then highlighting a net with a different color overwrites the previous highlight color. The highlight action is available when a single or multiple design objects are selected.
Tip: Highlighting a net, highlights the net and all the pins or ports (through the hierarchy) connected to the net.

To remove the highlight on a single design object, right-click the design object and click Remove . To remove the highlight on all design objects, click Unhighlight All in the SmartDesign toolbar.
Rename The Rename command opens a dialog box for a new net name to be entered to replace the current name. Enter a unique and valid net name and click OK.

If the name already exists, an error message is printed in the Log window, the Rename dialog box closes, and the name is not changed.
Delete The Delete command deletes the selected net. When multiple nets are selected, all are deleted.
Note: Not all design objects can be deleted. For example, PAD ports and nets cannot be deleted.