69 lines
1.7 KiB
Verilog
69 lines
1.7 KiB
Verilog
/*
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* Copyright (c) 2002 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 checks that ! of x works properly.
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*/
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module main;
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reg x;
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reg [1:0] xx;
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initial begin
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if (1'bx !== 1'bx) begin
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$display("FAILED -- simple constant x does't compare.");
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$finish;
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end
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if (1'bx !== !1'bx) begin
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$display("FAILED -- !1'bx comes out wrong.");
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$finish;
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end
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x = 1'bx;
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if (x !== 1'bx) begin
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$display("FAILED -- variable x comes out wrong.");
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$finish;
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end
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x = !x;
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if (x !== 1'bx) begin
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$display("FAILED -- ! of variable x comes out wrong.");
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$finish;
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end
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xx = 2'bx0;
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if (xx !== 2'bx0) begin
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$display("FAILED -- variable x comes out wrong.");
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$finish;
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end
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x = !xx;
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if (x !== 1'bx) begin
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$display("FAILED -- ! of variable xx comes out wrong.");
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$finish;
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end
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$display("PASSED");
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end
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endmodule // main
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