count_ones_b0.v

来自「VerilogHDL_advanced_digital_design_code_」· Verilog 代码 · 共 31 行

module count_ones_b0 (bit_count, data, clk, reset);
  parameter 				data_width = 4;
  parameter 				count_width = 3;
  output 		[count_width-1: 0]		bit_count;
  input 		[data_width-1: 0] 		data;
  input 					clk, reset;
  reg 		[count_width-1: 0] 	count, bit_count;
  reg 		[data_width-1: 0] 		temp;
  integer 				index;

  always begin: wrapper_for_synthesis 
    @ (posedge clk) begin: machine
      if (reset) begin bit_count = 0;  disable machine; end
      else 
        count = 0; bit_count = 0; index = 0; temp = data;   
        forever  @ (posedge clk)  
          if (reset) begin bit_count = 0; disable machine; end
          else if (index < data_width-1) begin  
            count = count + temp[0];
            temp = temp >> 1;
            index = index + 1;
          end
          else begin 
            bit_count = count + temp[0];
            disable machine; 
          end
    end // machine
  end // wrapper_for_synthesis
endmodule