/* Map Tracer Ver0.90c for Nissan silvia(S14 J's,Q's and K's)...designed by seychelle59 2006.2.10 Fri.
 *       If your car is Q's(J's), address higher bit(A[15]) input terminal must be external pull-down.
 * -------------------------------------------------------------------------------------------------- */

module maptracer9(a, b, c, ce, di, do, sel, outb, reset_N, ind, QK);
  input [15:8] b;    //address(upper 8bits)
  input [3:0] a;     //address(lower 4bits)
  input ce;          //chipenable
  input sel;         //indicate select
  input [7:6]di;     //D[7:6]=feedback signal
  input reset_N;     //system reset
  input QK;          //J's,Q's(Low) or K's(High)
  output [3:0] outb; //X driver output
  output ind;        //regular or highoctane
  output c;          //Y driver latch signal
  output [1:0] do;   //feedback signal
  reg [3:0] outb;
  reg [1:0] do;
  reg c, ind;

always @(negedge reset_N or negedge ce) begin
  if (!reset_N) begin
       outb <= 4'b0000;
       ind  <= 1;
       c    <= 0;
       do   <= 2'b00;
  end else begin
     if (sel == 0) begin
        if (QK == 1) begin
           case(b)
             8'b11101101: //ignition for highoctane(K's)
               begin
                    outb <= a[3:0];
                    ind  <= 1;
                    c    <= 0;
                    do   <= (di[7] == 1) ? 2'b01 : 2'b10;
               end
             8'b11101000: //ignition for regular fuel(K's)
               begin 
                 outb <= a[3:0];
                 ind  <= 0;
                 c    <= 0;
                 do   <= (di[7] == 1) ? 2'b01 : 2'b10;
               end
             default:
               begin
                    outb <= outb;
                    ind  <= ind;
                    c    <= 1;
                    do   <= do;
               end
           endcase
        end else begin           
           case(b)
             8'b00001000: //iginition for highoctane(J's,Q's)
               begin
                 outb <= a[3:0];
                 ind  <= 1;
                 c    <= 0;
                 do   <= (di[7] == 1) ? 2'b01 : 2'b10;
               end
             8'b00001101: //ignition for regular fuel(J's,Q's)
               begin 
                 outb <= a[3:0];
                 ind  <= 0;
                 c    <= 0;
                 do   <= (di[7] == 1) ? 2'b01 : 2'b10;
               end
             default:
               begin
                 outb <= outb;
                 ind  <= ind;
                 c    <= 1;
                 do   <= do;
               end
           endcase
        end
     end else begin
        if (QK == 1) begin
           case(b)
             8'b11100001: //highoctane(K's)
               begin
                 outb <= a[3:0];
                 ind  <= 1;
                 c    <= 0;
                 do   <= (di[6] == 1) ? 2'b01 : 2'b11;
               end
             8'b11101110: //regular fuel(K's)
               begin
                 outb <= a[3:0];
                 ind  <= 0;
                 c    <= 0;
                 do   <= (di[6] == 1) ? 2'b01 : 2'b11;
               end
             default:
               begin
                 outb <= outb;
                 ind  <= ind;
                 c    <= 1;
                 do   <= do;
               end
           endcase
        end else begin
           case(b)
             8'b00000001: //highoctane(J's,Q's)
               begin
                 outb <= a[3:0];
                 ind  <= 1;
                 c    <= 0;
                 do   <= (di[6] == 1) ? 2'b01 : 2'b11;
               end
             8'b00001110: //regular fuel(J's,Q's)
               begin
                 outb <= a[3:0];
                 ind  <= 0;
                 c    <= 0;
                 do   <= (di[6] == 1) ? 2'b01 : 2'b11;
               end
             default:
               begin
                 outb <= outb;
                 ind  <= ind;
                 c    <= 1;
                 do   <= do;
               end
           endcase
        end
     end
  end
end

endmodule