Counting 1's & 0's

Behavioural Description Code:--

module count(

    input  [7:0] num,

    output reg [3:0] one_cnt,

    output reg [3:0] zero_cnt

);

integer i;

always @(*) begin

    one_cnt  = 0;

    zero_cnt = 0;

    for (i = 0; i < 8; i = i + 1) begin

        if (num[i] == 1'b1)

            one_cnt = one_cnt + 1;

        else

            zero_cnt = zero_cnt + 1;

    end

end

endmodule

Test Bench:--

module tb_count;

    reg [7:0] num;

    wire [3:0] one_cnt;

    wire [3:0] zero_cnt;

    count DUT (num, one_cnt, zero_cnt);

    initial begin

        num = 8'b00000000; #10;

        num = 8'b11111111; #10;

        num = 8'b10101010; #10;

        num = 8'b11001100; #10;

        num = 8'b11100011; #10;

        num = 8'b10010010; #10;

        $finish;

    end

endmodule

OUTPUT WAVEFORM:--

pin assignment:

i/p=j15,l16,m13,r15,r17,t18,u18,r13

o/p=h17,k15,j13,n14,r18,u17,v17,u16