Specifications

64 Chapter 4—Simulation
produce a DONT0Z output, which resolves correctly to a LOW on the out-
put—regardless of the state of IN1—using the rules described previously.
Conflict
The Conflict state (“C” on a logic probe) results when two device outputs
are connected and are of different or unknown states—taking into account
the rules described previously.
State Display
The Timing window displays the various signal states in different colors.
The following Timing window shows how the various signal states are dis-
played.
Stuck–At Levels
The LogicWorks simulator implements stuck–at levels to assist in setting
initial simulation states, testing for faults, and so on. When a signal is in a
stuck–at state, it will not change state, regardless of changes in devices
driving the line.
When the stuck–at status is set, the signal will retain the value it had at that
time—until some user action forces a change. When the stuck–at status is
removed, the signal will return to the value determined by the devices driv-
ing the line.
Setting Stuck Levels
A signal can be placed in a Stuck–High or Stuck–Low state by any of the
following means:
 Applying the name “0” or “1” to the signal;
 Typing “H” or “L” while viewing the signal value with the signal
probe tool; or,
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