| 哥,我写的是这个,可是仿真出来后led值一直不变,是哪儿错了吗?
 module led_water(clk,rst,led
 );
 input clk;
 input rst;
 output reg [3:0] led;
 reg [25:0] counter;
 parameter T=26'd49999999;
 
 always@(negedge rst or posedge clk)
 if(!rst)
 begin
 counter<=26'd0;
 led<=4'b1110;
 end
 else
 begin
 if(counter==T)
 begin
 led<={led[2:0],led[3:0]};
 counter<=26'd0;
 end
 else
 begin
 led<=led;
 counter<=counter+26'd1;
 end
 end
 
 
 endmodule
 |