| // DESCRIPTION: Verilator: Verilog Test module |
| // |
| // This file ONLY is placed into the Public Domain, for any use, |
| // without warranty, 2014 by Wilson Snyder. |
| |
| module t (/*AUTOARG*/ |
| // Inputs |
| clk |
| ); |
| input clk; |
| |
| integer cyc=0; |
| reg [63:0] crc; |
| reg [63:0] sum; |
| |
| parameter NPAD = 4; |
| |
| tri pad [NPAD-1:0]; // Array |
| wire [NPAD-1:0] data0 = crc[0 +: 4]; |
| wire [NPAD-1:0] data1 = crc[8 +: 4]; |
| wire [NPAD-1:0] en = crc[16 +: 4]; |
| |
| for (genvar g=0; g<NPAD; ++g) begin : gpad |
| Pad pad1 (.pad(pad[g]), |
| .ena(en[g]), |
| .data(data1[g])); |
| Pad pad0 (.pad(pad[g]), |
| .ena(!en[g]), |
| .data(data0[g])); |
| end |
| |
| // Test loop |
| always @ (posedge clk) begin |
| `ifdef TEST_VERBOSE |
| $write("[%0t] cyc==%0d crc=%x result=%x\n",$time, cyc, crc, result); |
| `endif |
| cyc <= cyc + 1; |
| crc <= {crc[62:0], crc[63]^crc[2]^crc[0]}; |
| sum <= {60'h0, pad[3], pad[2], pad[1], pad[0]} |
| ^ {sum[62:0],sum[63]^sum[2]^sum[0]}; |
| if (cyc==0) begin |
| // Setup |
| crc <= 64'h5aef0c8d_d70a4497; |
| sum <= 64'h0; |
| end |
| else if (cyc<10) begin |
| sum <= 64'h0; |
| end |
| else if (cyc<90) begin |
| end |
| else if (cyc==99) begin |
| $write("[%0t] cyc==%0d crc=%x sum=%x\n",$time, cyc, crc, sum); |
| if (crc !== 64'hc77bb9b3784ea091) $stop; |
| // What checksum will we end up with (above print should match) |
| `define EXPECTED_SUM 64'he09fe6f2dfd7a302 |
| if (sum !== `EXPECTED_SUM) $stop; |
| $write("*-* All Finished *-*\n"); |
| $finish; |
| end |
| end |
| |
| endmodule |
| |
| module Pad |
| (inout pad, |
| input ena, |
| input data); |
| assign pad = ena ? data : 1'bz; |
| endmodule |