Experimental requirements

Through the control of high and low bits, the input of 32-bit data A, B and operation mode is realized, the hexadecimal operation result of ALU is displayed through 8 digital tubes, and 4 operation signals ZF SF CF OF (judgment zero) are displayed through 4 LED lights , sign, carry, overflow judgment)

source code

top level module

`timescale 1ns / 1ps

module TOP(
    input CLK_100M,
    input[15:0] in_data,
    input ctrl_in,
    input rst_,
    input CLK_A,
    input CLK_B,
    input CLK_OP,
    input ShowA,
    input ShowB,
    output[7:0] AN,
    output[7:0] SEG,
    output[3:0] out_flags
    );
    
    wire[31:0] a;
    wire[31:0] b;
    wire[31:0] res;
    wire[31:0] alu_f;
    wire[3:0] in_flags;
    reg[31:0] out_data;
    
    DataInput A(in_data, ctrl_in, CLK_A, rst_, a);
    DataInput B(in_data, ctrl_in, CLK_B, rst_, b);  //数据输入
    ALU alu(a, b, in_data[3:0], res, in_flags);
    ALU_F f(res, in_flags, CLK_OP, rst_, alu_f, out_flags);
    LED led(CLK_100M, rst_, out_data, AN, SEG);
    
    
    always@(ShowA or ShowB)
    begin
        if(!ShowA)
            out_data = a;
        else if(!ShowB)
            out_data = b;
        else
            out_data = alu_f;
    end
    
endmodule

Data Entry Module

`timescale 1ns / 1ps

module DataInput(
    input[15:0] data_in,
    input ctrl_in,
    input clk,
    input rst_,
    output reg[31:0] data_out
    );
    
    always@(negedge clk or negedge rst_)
    begin
        if(!rst_)
            data_out <= 32'b0;
        else
        begin
            if(ctrl_in == 1'b0)
                data_out[15:0] <= data_in;
            else
                data_out[31:16] <= data_in;
        end
    end
    
endmodule

ALU operation module

`timescale 1ns / 1ps

module ALU(
    input[31:0] a,
    input[31:0] b,
    input[31:0] op,
    output reg[32:0] res,
    output reg[3:0] flags
    );
    // flags: ZF    SF    CF   OF (高位->低位)
    //        判零  符号  进位  判溢
    
    always@(*)
    begin
        case(op)
            4'b0000:
            begin
                res <= a + b;
                flags[1] = res[32];
                flags[0] = a[31] ^ b[31] ^ res[31] ^ res[32];
            end
            4'b0001: res <= a << b;
            4'b0010: res <= ($signed(a) < $signed(b)) ? 1 : 0;
            4'b0011: res <= (a < b) ? 1 : 0;
            4'b0100: res <= a ^ b;
            4'b0101: res <= a >> b;
            4'b0110: res <= a | b;
            4'b0111: res <= a & b;
            4'b1000:
            begin
                res <= a - b;
                flags[1] = res[32];
                flags[0] = a[31] ^ b[31] ^ res[31] ^ res[32];
            end
            4'b1001: res <= $signed(a) >>> b;
        endcase
        flags[3] = (res == 32'd0) ? 1 : 0;
        flags[2] = res[31];
    end

endmodule

result processing module

`timescale 1ns / 1ps

module ALU_F(
    input[32:0] res,
    input[3:0] in_flags,
    input clk,
    input rst_,
    output reg[32:0] alu_f,
    output reg[3:0] out_flags
    );
    
    always@(negedge clk or negedge rst_)
    begin
        if(!rst_)
            begin
                alu_f <= 32'b0;
                out_flags <= 4'b1000;
            end
        else if(clk)
            begin
                alu_f <= res;
                out_flags <= in_flags;
            end
    end
    
endmodule

Scan digital tube module

Scan the top layer of the nixie tube

`timescale 1ns / 1ps

module LED(
    input clk_100M,
    input rst_,
    input[31:0] data,
    output[7:0] AN,
    output[7:0] SEG
);
    wire clk_ref; //数码管刷新频率：500hz
    wire clk_inc; //数字刷新频率：10hz
     
    Fdiv fdiv(clk_100M,32'd100000,clk_ref);
    Scanner scanner(data,rst_,clk_ref,AN,SEG);
endmodule

Divider

`timescale 1ns / 1ps

module Fdiv(
    input clk_in,
    input [31:0] count,
    output reg clk_out
    );
    reg[31:0] num;
    
    always@(posedge clk_in)
    begin
        if(num == count)
            begin
                clk_out <= ~clk_out;
                num <= 1'b0;
            end
        else
            num <= num + 1'b1;
    end
    
endmodule

Nixie tube display

`timescale 1ns / 1ps

module Scanner(
    input[31:0] data,
    input rst_,
    input clk_ref,
    output reg[7:0] AN,
    output reg[7:0] SEG
    );
reg[3:0] data_x;
reg[2:0] bit;

always@(negedge rst_ or posedge clk_ref)
begin
    if(!rst_)
        bit <= 3'd0;
    else
        bit <= bit + 1'b1;
end

always@(*)
    begin
        case(bit)
            3'b000: begin AN <= 8'b1111_1110; data_x <= data[3:0]; end
            3'b001: begin AN <= 8'b1111_1101; data_x <= data[7:4]; end
            3'b010: begin AN <= 8'b1111_1011; data_x <= data[11:8]; end
            3'b011: begin AN <= 8'b1111_0111; data_x <= data[15:12]; end
            3'b100: begin AN <= 8'b1110_1111; data_x <= data[19:16]; end
            3'b101: begin AN <= 8'b1101_1111; data_x <= data[23:20]; end
            3'b110: begin AN <= 8'b1011_1111; data_x <= data[27:24]; end
            3'b111: begin AN <= 8'b0111_1111; data_x <= data[31:28]; end
         endcase
         
         case(data_x)
            4'b0000: SEG <= 8'b0000_0011;
            4'b0001: SEG <= 8'b1001_1111;
            4'b0010: SEG <= 8'b0010_0101;
            4'b0011: SEG <= 8'b0000_1101;  
            4'b0100: SEG <= 8'b1001_1001;
            4'b0101: SEG <= 8'b0100_1001;
            4'b0110: SEG <= 8'b0100_0001;
            4'b0111: SEG <= 8'b0001_1111;
            4'b1000: SEG <= 8'b0000_0001;
            4'b1001: SEG <= 8'b0000_1001;
            4'b1010: SEG <= 8'b0001_0001;
            4'b1011: SEG <= 8'b1100_0001;
            4'b1100: SEG <= 8'b0110_0011;
            4'b1101: SEG <= 8'b1000_0101;
            4'b1110: SEG <= 8'b0110_0001;
            4'b1111: SEG <= 8'b0111_0001;
        endcase
     end
endmodule

emulation code

`timescale 1ns / 1ps

module ALU_top_sim();
    reg[31:0] a;
    reg[31:0] b;
    reg[3:0] op;
    wire[32:0] res;
    wire[3:0] flags; //顺序：ZF、SF、CF、OF

initial
        begin
            a = 32'h8000_0003;
            b = 32'h0000_0001;
    
            #100
            op = 4'b0000;   //加法
           
            #100
            op = 4'b0001;   //逻辑左移
            
            #100
            op = 4'b0010;   //有符号数比较          

            #100
            op = 4'b0011;   //无符号数比较            

            #100
            op = 4'b0100;   //异或
            
            #100
            op = 4'b0101;   //逻辑右移
            
            #100
            op = 4'b0110;   //按位或
            
            #100
            op = 4'b0111;   //按位与
           
            #100
            op = 4'b1000;   //减法
            
            #100
            op = 4'b1001;   //算术右移
        end    
    ALU alu_sim(a,b,op,res,flags);

endmodule

Structure layer diagram

pin configuration

set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN E3} [get_ports CLK_100M]

set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN V5} [get_ports in_data[15]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN T4} [get_ports in_data[14]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN V6} [get_ports in_data[13]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN T5} [get_ports in_data[12]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN T6} [get_ports in_data[11]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN V7} [get_ports in_data[10]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN R8} [get_ports in_data[9]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN U9} [get_ports in_data[8]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN T9} [get_ports in_data[7]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN V10} [get_ports in_data[6]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN R10} [get_ports in_data[5]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN U11} [get_ports in_data[4]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN R11} [get_ports in_data[3]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN U12} [get_ports in_data[2]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN T13} [get_ports in_data[1]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN V14} [get_ports in_data[0]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN T14} [get_ports ctrl_in]

set_property CLOCK_DEDICATED_ROUTE FALSE [get_nets rst_]
set_property CLOCK_DEDICATED_ROUTE FALSE [get_nets CLK_A]
set_property CLOCK_DEDICATED_ROUTE FALSE [get_nets CLK_B]
set_property CLOCK_DEDICATED_ROUTE FALSE [get_nets CLK_OP]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN N17} [get_ports rst_]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN P18} [get_ports CLK_A]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN P17} [get_ports CLK_B]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN R18} [get_ports CLK_OP]

set_property CLOCK_DEDICATED_ROUTE FALSE [get_nets ShowA]
set_property CLOCK_DEDICATED_ROUTE FALSE [get_nets ShowB]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN U18} [get_ports ShowA]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN U17} [get_ports ShowB]

set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN U6} [get_ports out_flags[3]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN R5} [get_ports out_flags[2]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN U7} [get_ports out_flags[1]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN R6} [get_ports out_flags[0]]

set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN C9} [get_ports AN[7]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN C10} [get_ports AN[6]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN D10} [get_ports AN[5]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN C11} [get_ports AN[4]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN M17} [get_ports AN[3]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN J14} [get_ports AN[2]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN K13} [get_ports AN[1]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN P14} [get_ports AN[0]]

set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN F14} [get_ports SEG[7]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN N14} [get_ports SEG[6]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN J13} [get_ports SEG[5]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN G13} [get_ports SEG[4]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN F13} [get_ports SEG[3]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN G14} [get_ports SEG[2]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN M13} [get_ports SEG[1]]
set_property -dict {IOSTANDARD LVCMOS18 PACKAGE_PIN H14} [get_ports SEG[0]]

【FPGA】Multifunctional ALU