Digital simulator commands
1. The following additional ":" commands are available with the
Digital LOG simulator. Except for STABILIZE they may be used
in "log.cnf" files by preceding them with the word "16:", as
in "16: stabdelay 2.5".
DIGON Turn digital simulation ON. This is the normal case.
DIGOFF Turn digital simulation OFF. This command is similar
the regular OFF command, except only the digital
simulator is affected. If several simulators are
being run at once (say, digital and analog), the
other simulators will proceed unaffected.
DIGONOFF ON/OFF
Turn digital simulation ON or OFF.
STABDELAY time
Set amount of time to wait for circuit stabilization
(see STABILIZE) to "time" seconds. Default is 5.0.
With no argument, the command shows the current value.
STABILIZE Attempt to stabilize an oscillating circuit. Because
all digital gates have identical, exact propagation
delays, oscillations can develop in feedback circuits
that would never arise in a real circuit, where the
propagation delays are not so exactly balanced. The
STABILIZE command randomizes the propagation delays of
gates in order to kill such oscillations. Of course,
a circuit that really is oscillating will continue
to do so. The "stabilization" effect wears off after
about five seconds, usually plenty of time.
DIGSTEP time-step
Set the amount of simulated time per digital timestep.
Since every digital time step is the same, this value
normally does matter unless you are using the digital
simulator along with another simulator which has a more
concrete idea of time (such as AnaLOG). The default
value is "10ns", i.e., 1E-8 seconds. The value may
be specified in engineering or real-number notation.
With no argument, the command shows the current value.
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