Virtuoso Schematic Composer User Guide

Creating Schematics

3. Click OK.

Adding Wires

A wire is a line that connects a pin and an instance or a line that intersects another wire. When you draw a wire between a pin and an instance, you create a net.

■Adding Narrow or Wide Wires on page 155

■Using Wire Snap and Gravity Options on page 155

■Using Wire Draw, Width, and Route Options on page 155

■Using Wire Flight Lines Option on page 156

■Routing Flight Lines on page 157

■Manipulating Wires with Only the Mouse on page 158

■Adding Wires to Schematic Instance Pins using SKILL on page 158

Virtuoso Schematic Composer User Guide

Creating Schematics

Adding Narrow or Wide Wires

To add wires, do the following:

1.Choose Add – Wire (narrow) or Add – Wire (wide).

You create buses by naming the wire using a specific notation.

2.Click on the wire starting point (for example, at a pin).

3.Click again for each wire segment.

As you move the pointer, a small diamond shape appears over the connection object closest to the pointer. The diamond jumps from one connection object to another as you move the pointer around the design window.

4.To end the wire, do one of the following:

Click a schematic pin, an instance pin, or another wire or double-click on a new wire endpoint.

Press s to snap to the nearest object that shows a diamond shape.

Shortcut: To create a wire from an instance pin, use the OSM or object direct manipulation.

Note: To terminate wires to pins that have been placed within a selection box, you must be in draw mode (not route mode).

Using Wire Snap and Gravity Options

To turn the wire snap or gravity option on or off, do the following:

1.Choose Options – Editor.

The Editor Options form appears.

2.Turn the Wire Snapping or Gravity field on or off.

Using Wire Draw, Width, and Route Options

To change wire draw, width, and route options, do the following:

1.Choose Add – Wire.

2.Press F3.

Virtuoso Schematic Composer User Guide

Creating Schematics

The Add Wire form appears.

Add Wire

3.Change the Draw Mode, Width, and Route Method options as follows:

The full or direct routing method cannot complete the connection wire. In this case, use a draw mode other than route to manually enter the wire.

The selection area boxes around two instances overlap each other and the full or direct wire connection cannot be made. In this case, move the instances apart to make room for the wire to pass through.

Using Wire Flight Lines Option

You might find it easier to use flight lines (dotted lines) while you are initially creating a schematic so that you will have more space to add instances. You use a flight line to show an intended logic connection. After all the instances are in place, you can let the system route the wires for you automatically to establish a physical connection represented by solid wires.

To draw flight lines to indicate an intended connection, do the following:

1.Choose Add – Wire.

2.Press F3.

3.Set Draw Mode to route.

4.Set Route Method to flight.

Virtuoso Schematic Composer User Guide

Creating Schematics

5. Draw a direct line between two objects.

I1

A

B Y

C

Flight line

nand3

TERM1

Routing Flight Lines

To convert wires to normal wires after adding them using the flight route method on the Add Wire form, do the following:

1.Choose Edit – Route Flight.

2.Click on a flight line to route.

The system routes the logical connections.

To change the route method, do the following:

1.Choose Edit – Route Flight.

2.Press the F3 key.

The Route Flight Line form appears.

Route Flight Line

3.Select a route method.

To draw complex lines to complete the connection, choose full.

To draw a direct line between two given points, choose direct.