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8bitworkshop/test/cli/verilog/t_tri_select.v

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// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed into the Public Domain, for any use,
// without warranty, 2008 by Lane Brooks.
// SPDX-License-Identifier: CC0-1.0
`define WIDTH 2
module top (
input OE1,
input OE2,
input [`WIDTH-1:0] A1,
input [`WIDTH-1:0] A2,
output [`WIDTH-1:0] Y1,
output [`WIDTH-1:0] Y2,
output [`WIDTH-1:0] Y3,
output [`WIDTH**2-1:0] W);
assign W[A1] = (OE2) ? A2[0] : 1'bz;
assign W[A2] = (OE1) ? A2[1] : 1'bz;
// have 2 different 'chips' drive the PAD to act like a bi-directional bus
wire [`WIDTH-1:0] PAD;
io_ring io_ring1 (.OE(OE1), .A(A1), .O(Y1), .PAD(PAD));
io_ring io_ring2 (.OE(OE2), .A(A2), .O(Y2), .PAD(PAD));
assign Y3 = PAD;
pullup p1(PAD);
// pulldown p1(PAD);
wire [5:0] fill = { 4'b0, A1 };
endmodule
module io_ring (input OE, input [`WIDTH-1:0] A, output [`WIDTH-1:0] O, inout [`WIDTH-1:0] PAD);
io io[`WIDTH-1:0] (.OE(OE), .I(A), .O(O), .PAD(PAD));
endmodule
module io (input OE, input I, output O, inout PAD);
assign O = PAD;
assign PAD = OE ? I : 1'bz;
endmodule