fix cunter, add testbench

1 files changed, 49 insertions, 0 deletions

diff --git a/nandgame/counter_tb.sv b/nandgame/counter_tb.sv
new file mode 100644
index 0000000..a7fab85
--- /dev/null
+++ b/nandgame/counter_tb.sv
@@ -0,0 +1,49 @@
+`timescale 1us/1us
+
+module counter_tb;
+
+logic clk_i, store;
+logic [15:0] in, res;
+
+counter uut (
+  .cl(clk_i),
+  .X(in),
+  .count(res),
+  .st(store)
+);
+
+string filename;
+initial begin
+`ifdef DUMP_FILE_NAME
+  filename=`DUMP_FILE_NAME;
+`else
+  filename="counter.lxt2";
+`endif
+  $dumpfile(filename); $dumpvars();
+  clk_i = 0;
+  store = 0;
+  in = 0;
+end
+
+always #10 clk_i = ~clk_i;
+
+initial begin
+  #200
+  @(posedge clk_i);
+  store = 1;
+  in = 16'd834;
+  repeat(3) begin
+    @(posedge clk_i);
+    assert (res == 834)
+    else   $error("Expected 834, got %d", res);
+  end
+  store = 0;
+  @(posedge clk_i);
+  assert (res == 835)
+  else   $error("Expected 835, got %d", res);
+  #30
+
+  $finish();
+end
+
+endmodule