//*************************************************** // File Name: traffic_light_controller.v // Date: October7,2008 // author: yilong.you // yilong.you@stu.xjtu.edu.cn //**************************************************/ module traffic_light_controller(clk,reset,light_color); input clk,reset; output[1:0] light_color; reg[1:0] light_color,state; reg[5:0]count; parameter S0=2'd0,green=2'd1,yellow=2'd2,red=2'd3; initial state=S0; always@(posedge clk or posedge reset)begin if(reset)begin state count end else case(state) S0: state green: begin count if(count==24) state end yellow:begin count if(count==26) state end red: begin count if(count==41) state end default: count endcase end always@(negedge clk) light_color endmodule
