iverilog/vvp/examples/sum.vvp

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:vpi_module "system";
; Copyright (c) 2001 Stephen Williams (steve@icarus.com)
;
; This source code is free software; you can redistribute it
; and/or modify it in source code form under the terms of the GNU
; General Public License as published by the Free Software
; Foundation; either version 2 of the License, or (at your option)
; any later version.
;
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
; GNU General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program; if not, write to the Free Software
; Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
; This example shows how to wire up a simple adder. The code below is
; like what might be generated from the Verilog:
;
; module main;
; reg [3:0] A, B;
; wire [3:0] Q = A + B;
:
: initial begin
; A = 2;
; B = 3;
; #1 $display("%b %b = %b", A, B, Q);
; end
; endmodule
;
; Notice the use of the .arith/sum statment, including the specification
; of the width (4 bits) and the order that the bits of the operands are
; passed to the statement.
S_main .scope "main";
A .var "A", 3, 0;
B .var "B", 3, 0;
add .arith/sum 4, A[0], A[1], A[2], A[3], B[0], B[1], B[2], B[3];
Q .net "Q", 3, 0, add[0], add[1], add[2], add[3];
start %set A[0], 0;
%set A[1], 1;
%set A[2], 0;
%set A[3], 0;
%set B[0], 1;
%set B[1], 1;
%set B[2], 0;
%set B[3], 0;
%delay 1;
%vpi_call "$display", "%b + %b == %b", A, B, Q;
%end;
.thread start;