move stuff around

1 files changed, 76 insertions, 0 deletions

diff --git a/playground/debounce_tb.v b/playground/debounce_tb.v
new file mode 100644
index 0000000..fb9430c
--- /dev/null
+++ b/playground/debounce_tb.v
@@ -0,0 +1,76 @@
+`timescale 1us/1us
+
+module debounce_tb;
+
+logic rst_i;
+logic clk_i;
+logic signal_i;
+logic signal_o;
+
+integer i = 0;
+
+debounce #(.STABLE_PERIOD(5)) uut (
+  .rst_i(rst_i),
+  .clk_i(clk_i),
+  .signal_i(signal_i),
+  .signal_o(signal_o)
+);
+
+string filename;
+initial begin
+`ifdef DUMP_FILE_NAME
+  filename=`DUMP_FILE_NAME;
+`else
+  filename="debounce.lxt2";
+`endif
+  $dumpfile(filename); $dumpvars();
+
+  clk_i = 0;
+  rst_i = 1'b1;
+  signal_i = 1'b1;
+  #1
+  rst_i = 1'b0;
+  #1
+  rst_i = 1'b1;
+end
+
+always #10 clk_i = ~clk_i;
+
+initial begin
+  // initial key press
+  @(negedge clk_i);
+  signal_i = ~signal_i;
+  assert (signal_o == 1'b1);
+ 
+  repeat(2) @(negedge clk_i);
+ 
+  signal_i = ~signal_i;
+  assert (signal_o == 1'b1);
+
+  // try bouncing
+
+  repeat(2) @(negedge clk_i);
+
+  for (i=0; i < 20; i = i + 1) begin
+    @(negedge clk_i);
+    signal_i = ~signal_i;
+    assert (signal_o == 1'b1);
+  end
+  @(negedge clk_i);
+  signal_i = ~signal_i;
+  assert (signal_o == 1'b1);
+
+  repeat(10) @(negedge clk_i);
+  assert (signal_o == 1'b0);
+
+  repeat(10) @(negedge clk_i);
+  signal_i = ~signal_i;
+
+  repeat(10) @(negedge clk_i);
+  assert (signal_o == 1'b1);
+
+  repeat(10) @(negedge clk_i);
+  $finish();
+end
+
+endmodule