/* * 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 */ /* * Test the select of a bit from a vector. */ module main; reg [3:0] a = 4'b0110; reg [1:0] s = 0; wire b = a[s]; initial begin #1 if (b !== 0) begin $display("FAILED -- a=%b, s=%b, b=%b", a, s, b); $finish; end s = 1; #1 if (b !== 1) begin $display("FAILED -- a=%b, s=%b, b=%b", a, s, b); $finish; end s = 2; #1 if (b !== 1) begin $display("FAILED -- a=%b, s=%b, b=%b", a, s, b); $finish; end s = 3; #1 if (b !== 0) begin $display("FAILED -- a=%b, s=%b, b=%b", a, s, b); $finish; end s = 2'bxx; #1 if (b !== 1'bx) begin $display("FAILED -- a=%b, s=%b, b=%b", a, s, b); $finish; end $display("PASSED"); end // initial begin endmodule // main