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Describe constant functor inputs in the symbol section.

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steve 2001-04-30 04:51:27 +00:00
parent 8057faccc1
commit f758010f01
1 changed files with 12 additions and 2 deletions
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14
vvp/README.txt
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@ -1,7 +1,7 @@
/*
* Copyright (c) 2001 Stephen Williams (steve@icarus.com)
*
* $Id: README.txt,v 1.19 2001/04/29 22:59:46 steve Exp $
* $Id: README.txt,v 1.20 2001/04/30 04:51:27 steve Exp $
*/
VVP SIMULATION ENGINE
@ -74,6 +74,9 @@ If the functor is part of a vector, then the symbol is the
vvp_ipoint_t for the first functor. The [] operator can then be used
to reference a functor other then the first in the vector.
There are some special symbols that in certain contexts have special
meanings. As inputs to functors, the symbols "C<0>", "C<1>", "C<x>"
and "C<z>" represent a constant driver of the given value.
FUNCTOR STATEMENTS:
@ -93,7 +96,14 @@ program. The references .ftype describes the behavoir of the
functor.
The <init> value is the 8-bit initial value of the 4 input ports. The
LSB is port 0, and the MSB port 3.
LSB is port 0, and the MSB port 3. If there are any constant inputs,
then the constantat the input becomes the initial value of the
corresponding input, replacing the value given in the <init>
position. Also, the output of the functor is calculated at compile
time given the init and constant input values. If the output is
different from "x", then a propagation event is schedule for the
functor so that when the simulation starts, the non-x value gets
propagated.
Almost all of the structural aspects of a simulation can be
represented by functors, which perform the very basic task of