p2s2p: Fix testbench

iverilog syntax error (needs space)
timing
use logic,

1 files changed, 82 insertions, 0 deletions

diff --git a/par_to_ser_to_par.tb.v b/par_to_ser_to_par.tb.v
new file mode 100644
index 0000000..c422d86
--- /dev/null
+++ b/par_to_ser_to_par.tb.v
@@ -0,0 +1,82 @@
+// converts back and forth
+// parallel > serial > parallel
+
+`timescale 1us/1us
+
+module par_to_ser_to_par_tb (
+);
+
+logic clk_i;
+logic rst_i;
+logic data_valid_i;
+logic [7:0] dat_i;
+
+logic dat_o;
+logic [7:0] dat_o2;
+logic send_valid;
+
+par_to_ser uut (
+  .clk_i(clk_i),
+  .rst_i(rst_i),
+  .data_valid_i(data_valid_i),
+  .dat_i(dat_i),
+  .dat_o(dat_o),
+  .dat_valid_o(send_valid)
+);
+
+ser_to_par uut2 (
+  .clk_i(clk_i),
+  .rst_i(rst_i),
+
+  .dat_valid_i(send_valid),
+  .dat_i(dat_o),
+
+  .dat_o(dat_o2),
+  .dat_valid_o()
+);
+
+string filename;
+initial begin
+`ifdef DUMP_FILE_NAME
+  filename=`DUMP_FILE_NAME;
+`else
+  filename="par_to_ser_to_par.lxt2";
+`endif
+  $dumpfile(filename); $dumpvars();
+  clk_i = 0;
+  rst_i = 1'b1;
+  data_valid_i = 1'b0;
+
+  #1
+  rst_i = 1'b0;
+  #1
+  rst_i = 1'b1;
+end
+
+always #10 clk_i = ~clk_i;
+
+initial begin
+  #13;
+  @(negedge clk_i);
+
+  for (integer i = 0; i < 255; i++) begin
+    // clock data in
+    dat_i = i;
+    data_valid_i = 1'b1;
+
+    // wait 1 cycle
+    @(negedge clk_i);
+    data_valid_i = 1'b0;
+
+    // let module do its work
+    repeat(10) @(negedge clk_i);
+  
+    assert(i == dat_o2)
+    else $error("Expected output to be h%x, but was h%x", i, dat_o2);
+
+  end
+
+  $finish();
+end
+
+endmodule