p5-20 連結運算子{}左移 右移1bit暫存器 適用於DE2-70 實驗板

p5-20 連結運算子{}左移 右移1bit暫存器

適用於DE2-70 實驗板

module SR_SL_1bit (SW, LEDR, LEDG);

input [17:0] SW; // toggle switches
output [17:0] LEDR; // red  LEDS   
  output [7:0] LEDG; // green LEDs
  
//set original program input , output 
wire [7:0]din;
wire l_r;
wire [7:0]sht_out;

   
    //mapping to hardware 
    assign LEDR = SW;
    assign din =SW[7:0];
    assign l_r=SW[17];
    
    //original program
    
reg [7:0]cnt;
always @(l_r or din)
begin
cnt=din;
if (l_r)
cnt ={cnt[6:0],1'b0};
else
  cnt ={1'b0,cnt[7:1]};

end

assign sht_out=cnt;



    //assign output LED
    assign LEDG[7:0]=sht_out;
    
endmodule    

/*
module sht_r_l(din,l_r,sht_out);
input [7:0]din;
input l_r;
output [7:0]sht_out;

reg[7:0] cnt;
always @(l_r or din)
begin 
cnt = din ;
if (l_r)
cnt = {cnt[6:0],1’b0};
else
cnt = {1’b0 ,cnt[7:1]};
end
assign sht_out=cnt;
endmodule
*/