National Instruments Graphical User Interface Ultiboard, Руководство пользователя

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Chapter 4 Working with Parts
© National Instruments Corporation 4-5 NI Ultiboard User Manual
Tools to Assist Part Placement
The following sections tell you how to use the tools that Ultiboard provides
to help you place parts and other elements on the design.
Working with Ratsnests
A ratsnest is a straight line connection between pads, indicating their
connectivity. The ratsnest identifies the pads which should be connected
according to the netlist, but which are not yet connected with traces.
Because these represent logical connections, and not the physical copper
connections referred to as traces in Ultiboard, they are just straight line
connections that can overlap parts and other ratsnest lines.
In Ultiboard, ratsnests are represented by colored lines, although they can
be dimmed so that they appear gray. They appear by default, exist on their
own layer, and can be controlled through the
Information section of the
Layers tab in the Design Toolbox . Refer to the Accessing Layers section
of Chapter 3, Setting Up a Design , for information about dimming and
hiding ratsnests in the Design Toolbox .
Tip You can also show or hide individual ratsnests from the Show Ratsnests column in
the Nets tab of the Spreadsheet View , and also from the Net Edit dialog box. Refer to the
Using the Netlist Editor section of Chapter 5, Working with Traces and Copper , for more
information.
The figure below shows the ratsnests as they connect pads in a design
without regard to running through parts.