| module b2d_tb; | |
| reg clk; | |
| integer cc, passed=0; | |
| reg fail=0; | |
| initial begin | |
| if ($test$plusargs("vcd")) begin | |
| $dumpfile("b2d.vcd"); | |
| $dumpvars(5,b2d_tb); | |
| end | |
| for (cc=0; cc<1400 ; cc=cc+1) begin | |
| clk=0; #4; | |
| clk=1; #4; | |
| end | |
| $display("%d tests passed", passed); | |
| if (fail) begin | |
| $display("FAIL"); | |
| $stop(0); | |
| end else begin | |
| $display("PASS"); | |
| $finish(0); | |
| end | |
| end | |
| reg [15:0] bdata, new_bdata, old_bdata; | |
| reg load=0; | |
| always @(posedge clk) begin | |
| bdata <= 16'bx; | |
| load <= 0; | |
| if (cc%120 == 10) begin | |
| old_bdata = new_bdata; | |
| load <= 1; | |
| new_bdata = 123; | |
| if (cc > 150) new_bdata = 60875; // 0xEDCB | |
| if (cc > 270) new_bdata = $random; | |
| bdata <= new_bdata; | |
| end | |
| end | |
| wire [3:0] nibble; | |
| wire nstrobe; | |
| b2d #(.sim_mode(1)) dut(.clk(clk), .bdata(bdata), .load(load), | |
| .nibble(nibble), .nstrobe(nstrobe)); | |
| integer result, power; | |
| always @(negedge clk) begin | |
| // if (load) $display("input %d", bdata); | |
| // if (nstrobe) $display("output %d", nibble); | |
| if (load) begin | |
| $display("result %d for input %d", result, old_bdata); | |
| if (result != old_bdata) begin $display("FAULT"); fail=1; end | |
| else passed = passed+1; | |
| result = 0; | |
| power = 1; | |
| end else if (nstrobe) begin | |
| result = result + nibble * power; | |
| power = power * 10; | |
| end | |
| end | |
| endmodule | |