Specifications

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4
Simulation
This chapter provides more detailed information on LogicWorks’
simulation capabilities.
General Information on Simulation
LogicWorks has the ability to perform a realistic simulation of any digital
circuit. Obviously, though, any simulation of any system must be limited in
detail and must make certain assumptions. In particular, when simulating
digital circuits, it must be understood that real circuits are never completely
“digital” in nature, and that they in fact have many “analog” properties
which affect how they operate.
LogicWorks is primarily intended to assist with the logical design of a cir-
cuit, and does not take into account factors such as line loading, power sup-
ply noise, rise and fall times, output drive, and so on. As more of these
factors are taken into account, the simulation becomes slower and less
interactive, which defeats the purpose for which LogicWorks was created.
Type of Simulation
LogicWorks performs a discrete simulation of the signal changes in a logic
circuit, meaning that signal levels and time change only in steps, rather
than continuously. The program does not attempt to analyze your circuit,
but simply tracks signal–level changes through the devices. Thus, circuits
with feedback loops or other delay–dependent features will be simulated
correctly as long as they don’t rely on particular analog characteristics of
devices.
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