Specifications

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Device Symbol Editing
Device symbols are an important resource in your design creation process.
Whether you primarily use the symbols provided with LogicWorks, or you
create special libraries for your own use, the completeness and accuracy of
this data has a major effect on your design flow. Library files generally
outlast any one design and are used for many years across many projects.
In addition, many LogicWorks features, for example, gate packaging, rely
on specific steps being taken while creating a symbol. For these reasons,
LogicWorks provides a variety of features for creating and editing the sym-
bols themselves and for maintaining symbol library files.
This chapter covers these topics:
 The creation and maintenance of symbol library files.
 The creation and editing of individual device symbols using the device
symbol editor tool.
 Schematic operations that affect symbol definitions.
Working With Symbol Libraries
The symbols and related parameters for LogicWorks devices are stored in
data files called symbol libraries. For each device type in a library the fol-
lowing data is stored:
 General information on the type, such as number of pins, number
inputs, number of outputs, type name, default delay, default attributes,
position, orientation and type of each pin, etc.
 A picture representing the symbol for this part type.
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