| // DESCRIPTION: Verilator: Verilog Test module |
| // |
| // This file ONLY is placed into the Public Domain, for any use, |
| // without warranty, 2005 by Wilson Snyder. |
| |
| module t (/*AUTOARG*/ |
| // Inputs |
| clk |
| ); |
| |
| input clk; |
| integer cyc; initial cyc=0; |
| |
| reg [7:0] crc; |
| reg [2:0] sum; |
| wire [2:0] in = crc[2:0]; |
| wire [2:0] out; |
| |
| MxN_pipeline pipe (in, out, clk); |
| |
| always @ (posedge clk) begin |
| //$write("[%0t] cyc==%0d crc=%b sum=%x\n",$time, cyc, crc, sum); |
| cyc <= cyc + 1; |
| crc <= {crc[6:0], ~^ {crc[7],crc[5],crc[4],crc[3]}}; |
| if (cyc==0) begin |
| // Setup |
| crc <= 8'hed; |
| sum <= 3'h0; |
| end |
| else if (cyc>10 && cyc<90) begin |
| sum <= {sum[1:0],sum[2]} ^ out; |
| end |
| else if (cyc==99) begin |
| if (crc !== 8'b01110000) $stop; |
| if (sum !== 3'h3) $stop; |
| $write("*-* All Finished *-*\n"); |
| $finish; |
| end |
| end |
| endmodule |
| |
| module dffn (q,d,clk); |
| parameter BITS = 1; |
| |
| input [BITS-1:0] d; |
| output reg [BITS-1:0] q; |
| input clk; |
| |
| always @ (posedge clk) begin |
| q <= d; |
| end |
| |
| endmodule |
| |
| module MxN_pipeline (in, out, clk); |
| parameter M=3, N=4; |
| |
| input [M-1:0] in; |
| output [M-1:0] out; |
| input clk; |
| |
| // Unsupported: Per-bit array instantiations with output connections to non-wires. |
| //wire [M*(N-1):1] t; |
| //dffn #(M) p[N:1] ({out,t},{t,in},clk); |
| |
| wire [M*(N-1):1] w; |
| wire [M*N:1] q; |
| dffn #(M) p[N:1] (q,{w,in},clk); |
| assign {out,w} = q; |
| |
| endmodule |