module digital_clock( input iCLK_50,input [15:0] iSW,
 output [6:0] oHEX2_D, oHEX3_D, oHEX4_D, oHEX5_D, oHEX6_D, oHEX7_D,
 output [15:0] oLEDR,
 output [4:0] oLEDG,
 input [1:0] iKEY );

 reg [3:0] hour_ten;
 reg [3:0] hour_num;
 reg [3:0] min_ten;
 reg [3:0] min_num;
 reg [3:0] sec_ten;
 reg [3:0] sec_num;
 reg [25:0] counter;

 assign oLEDR = iSW;

 //0~9초가 표시될때 LED로 애니메이션을 보여줌
 sec_ani SA(.clk(iCLK_50), .sel(sec_num[3:0]), .out_led(oLEDG[4:0]));

 m_7seg D2(.control(sec_num[3:0]), .HEX(oHEX2_D));
 m_7seg D3(.control(sec_ten[3:0]), .HEX(oHEX3_D));
 m_7seg D4(.control(min_num[3:0]), .HEX(oHEX4_D));
 m_7seg D5(.control(min_ten[3:0]), .HEX(oHEX5_D));
 m_7seg D6(.control(hour_num[3:0]), .HEX(oHEX6_D));
 m_7seg D7(.control(hour_ten[3:0]), .HEX(oHEX7_D));

 always@(negedge iCLK_50) // Input 50Mhz external clock
 begin
  if(iKEY[0] == 1\'b0) //set time
   begin
    hour_ten <= iSW[15:12];
    hour_num <= iSW[11:8];
    min_ten <= iSW[7:4];
    min_num <= iSW[3:0];
    sec_ten <= 4\'d0;
    sec_num <= 4\'d0;
   end

  if(iKEY[1] == 1\'b0) //reset time
   begin
    hour_ten <= 4\'d0;
    hour_num <= 4\'d0;
    min_ten <= 4\'d0;
    min_num <= 4\'d0;
    sec_ten <= 4\'d0;
    sec_num <= 4\'d0;
   end
   
  if(counter[25:0] == 26\'d50000000) // 1 sec loop
   begin
    if(sec_num == 4\'d9)
     begin
      sec_num <= 4\'d0;
      sec_ten[3:0] <= sec_ten[3:0] + 4\'b0001;
     end
    else
     sec_num[3:0] <= sec_num[3:0] + 4\'b0001;

    if(sec_ten == 4\'d5 && sec_num == 4\'d9)
     begin
      sec_ten[3:0] <= 4\'b0000;
      sec_num[3:0] <= 4\'b0000;
      min_num[3:0] <= min_num[3:0] + 4\'b0001;
     end

     counter[25:0] <= 1\'b0;
   end
  else
   counter[25:0] <= counter[25:0] + 1\'b1;

  if(min_num == 4\'d10 )
    begin
    min_num[3:0] <= 1\'b0;
    min_ten[3:0] <= min_ten[3:0] + 4\'b0001;
   end

  if(min_ten[3:0] == 4\'d6 && min_num[3:0] == 4\'d0 )
   begin
    min_ten[3:0] <= 1\'b0;
    min_num[3:0] <= 1\'b0;
    hour_num[3:0] <= hour_num[3:0] + 4\'b0001;
   end

  if(hour_num == 4\'d10 )
   begin
    hour_num[3:0] <= 1\'b0;
    hour_ten[3:0] <= hour_ten[3:0] + 4\'b0001;
   end

  if( (hour_ten[3:0] == 4\'d2) && (hour_num[3:0] == 4\'d4) )
   begin
    hour_num[3:0] <= 4\'b0000;
    hour_ten[3:0] <= 4\'b0000;
   end
 end

endmodule

// 7-segment
module m_7seg (control, HEX);
 input [3:0] control;
 output [0:6] HEX;

// -------abcdefg - negative
// 0 0000 0000001;
// 1 0001 1001111;
// 2 0010 0010010;
// 3 0011 0000110;

// 4 0100 1001100;
// 5 0101 0100100;
// 6 0110 1100000;
// 7 0111 0001111;

// 8 1000 0000000;
// 9 1001 0001100;

 assign HEX[0] = (~control[3]&~control[2]&~control[1]&~control[0])
 |(~control[3]&~control[2]&~control[1]&control[0])
 |(~control[3]&control[2]&control[1]&control[0]);

 assign HEX[1] = (~control[3]&~control[2]&~control[1]&control[0])
 |(~control[3]&~control[2]&control[1]&~control[0])
 |(~control[3]&~control[2]&control[1]&control[0])
 |(~control[3]&control[2]&control[1]&control[0]);

 assign HEX[2] = ~((~control[3]&~control[2]&~control[1]&~control[0])
 |(~control[3]&~control[2]&control[1]&~control[0])
 |(~control[3]&control[2]&control[1]&~control[0])
 |(control[3]&~control[2]&~control[1]&~control[0]));

 assign HEX[3] = (~control[3]&~control[2]&~control[1]&control[0])
 |(~control[3]&control[2]&~control[1]&~control[0])
 |(~control[3]&control[2]&control[1]&control[0])
 |(control[3]&~control[2]&~control[1]&control[0]);

 assign HEX[4] = (~control[3]&~control[2]&control[1]&~control[0]);

 assign HEX[5] = (~control[3]&control[2]&~control[1]&control[0])
 |(~control[3]&control[2]&control[1]&~control[0]);

 assign HEX[6] = (~control[3]&~control[2]&~control[1]&control[0])
 |(~control[3]&control[2]&~control[1]&~control[0])
 |(~control[3]&control[2]&control[1]&~control[0]);

endmodule

//1초가 지날때마다 LED로 애니메이션 표시
module sec_ani(input clk,input [3:0] sel,
 output reg [4:0] out_led);

 always@(posedge clk)
 begin
  case(sel[3:0])
   4\'d0: out_led[4:0] <= 5\'b00000;
   4\'d1: out_led[4:0] <= 5\'b00001;
   4\'d2: out_led[4:0] <= 5\'b00011;
   4\'d3: out_led[4:0] <= 5\'b00111;
   4\'d4: out_led[4:0] <= 5\'b01111;
   4\'d5: out_led[4:0] <= 5\'b11111;
   4\'d6: out_led[4:0] <= 5\'b11110;
   4\'d7: out_led[4:0] <= 5\'b11100;
   4\'d8: out_led[4:0] <= 5\'b11000;
   4\'d9: out_led[4:0] <= 5\'b10000;
  endcase
 end

endmodule

여기에서 시를 1~12 분과 초를 00~29까지하고 시간은 주파수 반으로 쪼개서 0.5초로 나오게 만들었어
근데 시간을 1초씩 올라가는게 아니라 시 분 초가 3의 배수로 올라가게 만들어야 되는데 도통 감이 안잡히네

고수들 도와줘