clean up Rotator fpga code

diff --git a/ships/Rotator.ship b/ships/Rotator.ship
index 7c5c570..c6661c4 100644 (file)
--- a/ships/Rotator.ship
+++ b/ships/Rotator.ship
@@ -33,21 +33,34 @@ public void service() {
 
 == FPGA ==============================================================
 
-  wire [`DATAWIDTH*2-1:0] double;
-  assign double = { in_d[`DATAWIDTH-1:0], in_d[`DATAWIDTH-1:0] };
+  reg [(`DATAWIDTH-1):0] out_d;
+  assign out_d_ = out_d;
+
+  reg [5:0] shamt;
+  initial shamt = 0;
+
+  wire shamt_eq;
+  assign shamt_eq = (shamt[5:0] == (inAmount_d[5:0]));
 
   always @(posedge clk) begin
     if (!rst) begin
       `reset
     end else begin
-      if (!in_r        && in_a)       in_a    <= 0;
+      if (!in_r        && in_a && !inAmount_r)       in_a        <= 0;
       if (!inAmount_r  && inAmount_a) inAmount_a  <= 0;
-      if (out_r        && out_a)      out_r   <= 0;
+      if (out_r        && out_a)      out_r       <= 0;
       if (in_r && !in_a && inAmount_r && !inAmount_a && !out_r && !out_a) begin
-        in_a <= 1;
-        inAmount_a <= 1;
-        out_r <= 1;
-        out_d <= double >> (`DATAWIDTH - inAmount_d);
+        in_a  <= 1;
+        out_d <= in_d;
+        shamt <= 0;
+      end else if (in_a && inAmount_r && !inAmount_a && !out_r && !out_a) begin
+        if (!shamt_eq) begin
+           out_d <= { out_d[`DATAWIDTH-2:0], out_d[`DATAWIDTH-1] };
+           shamt <= shamt+1;
+        end else begin
+           inAmount_a <= 1;
+           out_r <= 1;
+        end
       end
     end
   end