Specifications

16 Chapter 2—Schematic Editing
function. For example, the analog components provided in the
discrete.clf library fall into this category.
 Subcircuit devices: These are symbols which have a simulation
function defined by an internal circuit. The 7400 devices provided with
LogicWorks fall into this category. The internal circuit for this kind of
symbol can be viewed by double-clicking on the symbol.
 Pseudo-devices: These are the symbols used for bus breakouts, power
and ground symbols, and so on. They do not represent an actual
physical device in a circuit, but they have specific meanings on the
schematic diagram.
 Simulation primitives: These are device symbols which have a built-
in simulation function when used with the LogicWorks simulator.
 See a description of LogicWorks primitive types in Chapter 9,
Primitive Devices.
Device Libraries
The symbols and related parameters for LogicWorks devices are stored in
data files called device libraries. Libraries can be opened and closed by dis-
playing the Parts Palette’s pop-up menu and using the Open and Close
commands, or by using entries in the initialization file.
For each device symbol in a library, the following data is stored:
 General information on the type, such as number of pins, number of
inputs, number of outputs, type name, default delay, default attributes,
position, orientation and type of each pin, and so on.
 A picture representing the symbol for this type.
 An optional internal circuit definition.
How Device Symbols are Created and Stored
Libraries are created and modified using the DevEditor tool, which is
described elsewhere in this manual.
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