Add parameter to s2p

1 files changed, 13 insertions, 11 deletions

diff --git a/ser_to_par.v b/ser_to_par.v
index fc6d22f..0a8c4c4 100644
--- a/ser_to_par.v
+++ b/ser_to_par.v
@@ -5,25 +5,27 @@
 // or generally, an enable pin.
 //
 
-module ser_to_par (
+module ser_to_par #(
+  parameter SHIFT_WIDTH = 8
+) (
   input rst_i,
   input clk_i,
+
+  input dat_valid_i,
   input dat_i,
-  output reg[7:0] dat_o
+
+  output reg[(SHIFT_WIDTH - 1):0] dat_o,
+  // ???
+  output dat_valid_o
 );
 
-// Learning:
-// Ugh, this is fucking stupid.
-// if I send out directly at the rising clock edge,
-// the output, when directly used again with the same clock,
-// will violate setup and hold times???
-//
 always @(posedge clk_i or negedge rst_i) begin
   if (!rst_i) begin
     dat_o <= 8'b0;
-  end else begin
-    dat_o[7] <= dat_i;
-    dat_o[6:0] <= dat_o[7:1];
+  end else if(dat_valid_i) begin
+    // shift into highest bit first, so it is subsequently shifted down
+    dat_o[SHIFT_WIDTH - 1] <= dat_i;
+    dat_o[(SHIFT_WIDTH - 2):0] <= dat_o[(SHIFT_WIDTH - 1):1];
   end
 end