sum3.v

多个Verilog和vhdl程序例子

//
// Sum three numbers and wait for next
// start signal
//
`timescale 100 ps/100 ps
module sum3(sum, ready, d, reset,start, clk);
output [7:0] sum;
input [7:0] d;
output ready;
input start, clk,reset;

reg [7:0] sum;
reg ready;
integer [3:0] i;
//integer i;

always begin :lbl
	#1;
	while(reset || !start) begin
		ready = 1;
		@(posedge clk);
	end
	for(i = 0;!reset &&  (i < 3'b100); i = i + 1) begin
		ready = 0;
		sum = (i?sum:0) + d;
		@(posedge clk);
	end
end

endmodule