afisare reversibila

Buna! Am facut un prog care afișează, folosind o cifra cu 7 segmente, codul numeric personal. As vrea sa incerc sa afisez si reversibil doar ca nu stiu cum.Ma puteti ajuta? Multumesc anticipat!
  Aici este prog pe care l'am facut:
module tema1_top(
    input clock,
  input reset,
  output [7:0] c, //semnale de control penntru segmente
  output [3:0]an //semnale de control pentru afisare
    );
wire [31:0] fir;

  assign an[0]=0;
  assign an[1]=1;
  assign an[2]=1;
  assign an[3]=1;

  
    segmente s( .adr(fir),
  .seg©);

  numarator n( .rst(reset),
   .clk(clock),
   .nr(fir));



endmodule

module segmente(
  input [31:0]adr,
    output reg [7:0]seg
  
    );
wire [3:0]fir;
assign fir[0]=adr[25];
assign fir[1]=adr[26];
assign fir[2]=adr[27];
assign fir[3]=adr[28];
always@(fir)
  begin
  case(fir)
  0:seg=8'b10100100;
  1:seg=8'b10010000;
  2:seg=8'b10110000;
  3:seg=8'b11000000;
  4:seg=8'b10110000;
  5:seg=8'b10100100;
  6:seg=8'b10010000;
  7:seg=8'b11111001;
  8:seg=8'b10110000;
  9:seg=8'b10100100;
  10:seg=8'b10000000;
  11:seg=8'b11000000;
  12:seg=8'b10110000;
  default:seg=8'b01111111;
endcase
end

endmodule

module numarator(
   input rst,
input clk,
   output reg [31:0]nr
);
always @ (posedge clk)
begin
  if (rst==1)
    nr <= 0;
  else
  nr <= nr +1;

end
endmodule

net "an[0]" loc="F17";
net "an[1]" loc="H17";
net "an[2]" loc="C18";
net "an[3]" loc="F15";
net "clock" loc="B8";
net "reset" loc="H13";
net "c[0]" loc="L18";
net "c[1]" loc="F18";
net "c[2]" loc="D17";
net "c[3]" loc="D16";
net "c[4]" loc="G14";
net "c[5]" loc="J17";
net "c[6]" loc="H14";
net "c[7]" loc="C17";