adder7.v

//This module is the highest level of the module.
// it includes all the input and output in the DE2-70
module adder7(
// Clock Input (50 MHz)
	input  CLOCK_50,
	//  Push Buttons
	input  [3:0]  KEY,
	//  DPDT Switches 
	input  [17:0]  SW,
	
	//  7-SEG Displays
	output  [6:0]  HEX0, HEX1, HEX2, HEX3, HEX4, HEX5, HEX6, HEX7,
	output [7:0] sum,
	output cout,
	// This is added to the convert the 8-bits to different HEX_
	output [3:0] ONES, TENS,
	output [1:0] HUNDREDS,
	output  [3:0] finalhundred,
	//  LEDs
	output  [8:0]  LEDG,  //  LED Green[8:0]
	output  [17:0]  LEDR, //  LED Red[17:0]
	//  GPIO Connections
	inout  [35:0]  GPIO_0, GPIO_1
);
//  set all inout ports to tri-state
	assign  GPIO_0    =  36'hzzzzzzzzz;
	assign  GPIO_1    =  36'hzzzzzzzzz;
	
	// Connect dip switches to red LEDs
	assign LEDR[17:0] = SW[17:0];
	wire [15:0] A;
	//always @(negedge KEY[3])
	//    A <= SW[15:0];
	// I am adding this code to

	seven_bit(cout,sum[6:0],SW[13:7],SW[6:0],1'b0);
	assign sum[7]=cout;

	// Now I call the BCD here to convert the result to various HEX display.
	BCD(sum[7:0],ONES, TENS,HUNDREDS);
	assign finalhundred = {2'b00,HUNDREDS[1:0]};
	hex_7seg dsp0(ONES,HEX0);
	hex_7seg dsp1(TENS,HEX1);
	hex_7seg dsp2(finalhundred,HEX2);
	assign HEX3 = blank;
	assign HEX4 = blank;
	assign HEX5 = blank;
	assign HEX6 = blank;
	assign HEX7 = blank;
	
	wire [6:0] blank = ~7'h00;
	assign A = SW[15:0];
endmodule


// The BCD module begin here.
module BCD (A,ONES, TENS, HUNDREDS);
	input [7:0] A; 
	output [3:0] ONES, TENS; 
	output [1:0] HUNDREDS; 
	wire [3:0] c1,c2,c3,c4,c5,c6,c7; 
	wire [3:0] d1,d2,d3,d4,d5,d6,d7;  
	assign d1 = {1'b0,A[7:5]}; 
	assign d2 = {c1[2:0],A[4]}; 
	assign d3 = {c2[2:0],A[3]}; 
	assign d4 = {c3[2:0],A[2]}; 
	assign d5 = {c4[2:0],A[1]}; 
	assign d6 = {1'b0,c1[3],c2[3],c3[3]}; 
	assign d7 = {c6[2:0],c4[3]}; 
	assign ONES = {c5[2:0],A[0]}; 
	assign TENS = {c7[2:0],c5[3]}; 
	assign HUNDREDS = {c6[3],c7[3]}; 
	add3 m1(d1,c1); 
	add3 m2(d2,c2); 
	add3 m3(d3,c3); 
	add3 m4(d4,c4); 
	add3 m5(d5,c5); 
	add3 m6(d6,c6); 
	add3 m7(d7,c7); 
endmodule


// This module is called from the previous module to calculate
// the 8-bits to three different HEX.
module add3(in,out); 
	input [3:0] in; 
	output [3:0] out; 
	reg [3:0] out;  
	always @ (in)  
	case (in)  
		4'b0000: out <= 4'b0000;  
		4'b0001: out <= 4'b0001;  
		4'b0010: out <= 4'b0010;  
		4'b0011: out <= 4'b0011;  
		4'b0100: out <= 4'b0100;  
		4'b0101: out <= 4'b1000;  
		4'b0110: out <= 4'b1001;  
		4'b0111: out <= 4'b1010;  
		4'b1000: out <= 4'b1011;  
		4'b1001: out <= 4'b1100;  
		default: out <= 4'b0000;  
endcase 

endmodule 
module hex_7seg(hex_digit,seg);
	input [3:0] hex_digit;
	output [6:0] seg;
	reg [6:0] seg;
	// seg = {g,f,e,d,c,b,a};
	// 0 is on and 1 is off
	
	always @ (hex_digit)
	case (hex_digit)
		4'h0: seg = ~7'h3F;
		4'h1: seg = ~7'h06;     // ---a----
		4'h2: seg = ~7'h5B;     // |      |
		4'h3: seg = ~7'h4F;     // f      b
		4'h4: seg = ~7'h66;     // |      |
		4'h5: seg = ~7'h6D;     // ---g----
		4'h6: seg = ~7'h7D;     // |      |
		4'h7: seg = ~7'h07;     // e      c
		4'h8: seg = ~7'h7F;     // |      |
		4'h9: seg = ~7'h67;     // ---d----
		4'ha: seg = ~7'h77;
		4'hb: seg = ~7'h7C;
		4'hc: seg = ~7'h39;
		4'hd: seg = ~7'h5E;
		4'he: seg = ~7'h79;
		4'hf: seg = ~7'h71;
	endcase
endmodule

//Here I have the four binary Adder module (ADDER Logic)
module f_adder(sum,cout,cin,inp1,inp2);
	input cin, inp1, inp2;
	output sum,cout;
	wire w1,w2,w3;
	xor x1(w1,inp1,inp2);
	xor x2(sum,w1,cin);
	and a1(w2,inp1,inp2);
	and a2(w3,w1,cin);
	or(cout,w2,w3);
endmodule

module seven_bit(cout,sum,x,y,cin);
	input [6:0] x,y;
	input cin;
	output [6:0] sum;
	output cout;
	wire d1,d2,d3,d4,d5,d6;
	f_adder f1(sum[0],d1,x[0],y[0],cin);
	f_adder f2(sum[1],d2,x[1],y[1],d1);
	f_adder f3(sum[2],d3,x[2],y[2],d2);
	f_adder f4(sum[3],d4,x[3],y[3],d3);
	f_adder f5(sum[4],d5,x[4],y[4],d4);
	f_adder f6(sum[5],d6,x[5],y[5],d5);
	f_adder f7(sum[6],cout,x[6],y[6],d6);
endmodule