在quartus软件中，利用if语句设计一个三位二进制数A,B的比较电路，比较结果（A<B）,（A>B）,（A==B）,（A===B）的结果分别输出给信号LT,GT,EQ,AEQ;写出代码

在Quartus软件中，设计一个使用if语句进行三位二进制数A和B比较的电路，通常涉及到Verilog HDL语言。这是一个基本的示例，假设A和B都是3位宽的二进制数：

module compare(A : in std_logic_vector(2 downto 0), B : in std_logic_vector(2 downto 0),
               LT : out wire, GT : out wire, EQ : out wire, AEQ : out wire);

input [2:0] A;
input [2:0] B;
output LT;
output GT;
output EQ;
output AEQ;

wire result [2:0];   // Temporary storage for the comparison

always @(*) begin
    if (A < B) begin
        LT = '1';      // Output high when A is less than B
        GT = '0';
        EQ = '0';
        AEQ = '0';
    end else if (A > B) begin
        LT = '0';
        GT = '1';      // Output high when A is greater than B
        EQ = '0';
        AEQ = '0';
    end else if (A == B) begin
        LT = '0';
        GT = '0';
        EQ = '1';      // Output high when A equals B
        AEQ = '1';     // Output 'A === B' as an extended equality check (usually not supported by hardware)
    end else begin
        LT = 'X';       // If none of the above conditions match, assume unknown (usually inferred as don't care)
        GT = 'X';
        EQ = 'X';
        AEQ = 'X';
    end
end

// Assuming the output is latched to the desired signals after this always block
assign LT = result[2];
assign GT = result[1];
assign EQ = result[0];
assign AEQ = result[3];   // Since we're using an extended equality check, 'AEQ' won't be used in real hardware design

endmodule

注意：在实际的硬件设计中，"A===B"这种形式的检查通常是通过软件层面上处理，因为大部分FPGA/CPLD器件并不直接支持这样的操作。此外，上述代码中对于未知条件的处理，通常会在设计时进行优化。