57 lines
1.6 KiB
Coq
57 lines
1.6 KiB
Coq
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/*
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* Copyright (c) 2000 Stephen Williams (steve@icarus.com)
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*
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* This source code is free software; you can redistribute it
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* and/or modify it in source code form under the terms of the GNU
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* General Public License as published by the Free Software
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* Foundation; either version 2 of the License, or (at your option)
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* any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
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*/
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/*
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* This module tests the basic behavior of a tri0 register. We use a ?:
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* to turn on/off the driver to the tri0 net and watch its value.
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* A tri0 net should pull to 0 when undriven, and follow the driver
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* otherwise.
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*/
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module main;
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reg enable, val;
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tri0 t0 = enable ? val : 1'bz;
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initial begin
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enable = 0;
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val = 0;
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#1 if (t0 !== 1'b0) begin
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$display("FAILED -- undriven t0 == %b", t0);
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$finish;
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end
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enable = 1;
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#1 if (t0 !== 1'b0) begin
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$display("FAILED -- driven-0 t0 == %b", t0);
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$finish;
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end
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val = 1;
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#1 if (t0 !== 1'b1) begin
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$display("FAILED -- driven-1 t0 == %b", t0);
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$finish;
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end
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$display("PASSED");
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end // initial begin
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endmodule // main
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