| // DESCRIPTION: Verilator: Verilog Test module |
| // |
| // This file ONLY is placed into the Public Domain, for any use, |
| // without warranty, 2018 by Wilson Snyder. |
| |
| module t (/*AUTOARG*/ |
| // Inputs |
| clk |
| ); |
| |
| input clk; |
| reg signed i; |
| wire signed o1; |
| wire signed o2; |
| |
| integer cyc; initial cyc=0; |
| |
| sub1 sub1 (.i(i), .o(o1)); |
| sub2 sub2 (.i(o1), .o(o2)); |
| |
| always @ (posedge clk) begin |
| cyc <= cyc + 1; |
| if (cyc==0) begin |
| i <= 1'b0; |
| end |
| else if (cyc==1) begin |
| if (o2 != 1'b0) $stop; |
| i <= 1'b1; |
| end |
| else if (cyc==2) begin |
| if (o2 != 1'b1) $stop; |
| end |
| if (cyc==3) begin |
| $write("*-* All Finished *-*\n"); |
| $finish; |
| end |
| end |
| endmodule |
| |
| //msg2540 |
| module sub1 ( |
| input signed i, |
| output wire signed o); |
| assign o = ~i; |
| endmodule |
| |
| module sub2 (i,o); |
| input signed i; |
| output signed o; |
| wire signed o = ~i; |
| endmodule |