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// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain, for
// any use, without warranty, 2014 by Wilson Snyder.
// SPDX-License-Identifier: CC0-1.0
module t (/*AUTOARG*/
// Inputs
clk
);
input clk;
integer cyc; initial cyc = 0;
reg [63:0] crc;
reg [63:0] sum;
reg out1;
reg [4:0] out2;
sub sub (.in(crc[23:0]), .out1(out1), .out2(out2));
always @ (posedge clk) begin
`ifdef TEST_VERBOSE
$write("[%0t] cyc==%0d crc=%x sum=%x in[3:0]=%x out=%x,%x\n", $time, cyc, crc, sum, crc[3:0], out1,out2);
`endif
cyc <= cyc + 1;
crc <= {crc[62:0], crc[63] ^ crc[2] ^ crc[0]};
sum <= {sum[62:0], sum[63]^sum[2]^sum[0]} ^ {58'h0,out1,out2};
if (cyc==0) begin
// Setup
crc <= 64'h00000000_00000097;
sum <= 64'h0;
end
else if (cyc==99) begin
$write("[%0t] cyc==%0d crc=%x sum=%x\n", $time, cyc, crc, sum);
`define EXPECTED_SUM 64'h10204fa5567c8a4b
if (sum !== `EXPECTED_SUM) $stop;
$write("*-* All Finished *-*\n");
$finish;
end
end
endmodule
module sub (/*AUTOARG*/
// Outputs
out1, out2,
// Inputs
in
);
input [23:0] in;
output reg out1;
output reg [4:0] out2;
always @* begin
case (in[3:0]) inside
default: {out1,out2} = {1'b0,5'h0F}; // Note not last item
4'h1, 4'h2, 4'h3: {out1,out2} = {1'b1,5'h01};
4'h4: {out1,out2} = {1'b1,5'h04};
[4'h6:4'h5]: {out1,out2} = {1'b1,5'h05}; // order backwards, will not match
4'b100?:/*8,9*/ {out1,out2} = {1'b1,5'h08};
[4'hc:4'hf]: {out1,out2} = {1'b1,5'h0C};
endcase
end
endmodule
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