| module testbench; |
| reg clk; |
| |
| initial begin |
| // $dumpfile("testbench.vcd"); |
| // $dumpvars(0, testbench); |
| |
| #0 clk = 0; |
| repeat (10000) begin |
| #5 clk = 1; |
| #5 clk = 0; |
| end |
| |
| $display("OKAY"); |
| end |
| |
| |
| reg [7:0] a; |
| reg [7:0] b; |
| wire [7:0] c_p; |
| wire [7:0] c; |
| |
| always @(posedge clk) |
| begin |
| a = a + 3; |
| b = b + 7; |
| end |
| |
| assign c_p = a[$signed(b) +: 8]; |
| |
| top uut (a, b, c); |
| |
| uut_checker c_test(.clk(clk), .A(c_p), .B(c)); |
| |
| endmodule |
| |
| module uut_checker(input clk, input [7:0] A, input [7:0] B); |
| always @(posedge clk) |
| begin |
| #1; |
| if (A != B) |
| begin |
| $display("ERROR: ASSERTION FAILED in %m:",$time," ",A," != ",B); |
| $stop; |
| end |
| end |
| endmodule |