题解 | #自动贩售机1#

//注意一旦存储数据大于等于3 置零
`timescale 1ns/1ns
module seller1(
	input wire clk  ,
	input wire rst  ,
	input wire d1 ,
	input wire d2 ,
	input wire d3 ,
	
	output reg out1,
	output reg [1:0]out2
);
//*************code***********//
reg [3:0] da;
always@(posedge clk or negedge rst)begin
if(!rst)
da<=0;
else if(d1)
da<=da+1;
else if(d2)
da<=da+2;
else if(d3)
da<=da+4;
else if(da>=3)
da<=0;
else
da<=da;
end

always@(posedge clk or negedge rst)begin
if(!rst)begin
out1<=0;
out2<=0;
end
else if(da>=3)begin
	out1<=1;
	out2<=da-3;
	da<=0;
end
else begin
	out1<=0;
	out2<=0;
end
end
//*************code***********//
endmodule