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==== 一、 实验目的与意义 ====
//检测到时间闸门信号的高电平时,熄灭led,再次检测到时点亮led,如此循环。 reg led_r; reg [2:0]led_state; always@(posedge clk_25m or negedge rst_n) begin if(!rst_n) begin led_r <= led_off; led_state <= `state_idle; //上电复位后进入空闲状态 end else begin case(led_state) `state_idle:begin led_state <= `state_led_on;//进入点亮led状态 led_r <= led_off; end `state_led_on:begin led_r <= led_on; if(state_sig) begin led_state <= `state_led_off; end else begin led_state <= led_state; end end `state_led_off:begin led_r <= led_off; if(state_sig) begin led_state <= `state_led_on; end else begin led_state <= led_state; end end endcase end end
1、通过Signaltap采样状态机跳转信号及状态切换,观察信号变化。