// DESCRIPTION: Verilator: Verilog Test module // // This file ONLY is placed under the Creative Commons Public Domain. // SPDX-FileCopyrightText: 2015 Mike Thyer // SPDX-License-Identifier: CC0-1.0 module t ( input clk ); int cycle = 0; // verilator lint_off UNOPTFLAT reg [7:0] a_r; wire [7:0] a_w; reg [7:0] b_r; reg [7:0] c_d_r, c_q_r; assign a_w = a_r; always @(*) begin a_r = 0; b_r = a_w; // Substituting the a_w assignment to get b_r = 0 is wrong, as a_r is not "complete" a_r = c_q_r; c_d_r = c_q_r; end // stimulus + checks always @(posedge clk) begin cycle <= cycle + 1; if (cycle == 0) begin c_q_r <= 8'b0; end else begin c_q_r <= c_d_r + 1; `ifdef TEST_VERBOSE $display("[%0t] a_r=%0d, b_r=%0d", $time, a_r, b_r); // a_r and b_r should always be the same `endif end if (cycle >= 10) begin if (b_r == 9) begin $write("*-* All Finished *-*\n"); $finish; end else begin $stop; end end end endmodule