lcu.v

一组两个电梯的控制器

module scu(cfloor,status,cmd,incmd,reset,clk,load_enable,open);
input [2:0] cmd;
input reset;
input clk;
input load_enable;
input[2:0] incmd; 
reg[2:0] lastcmd;
reg[2:0] tempcmd;
reg[5:0]  CNT;
output open;reg open;
output[2:0] cfloor; reg[2:0] cfloor;
output[1:0] status; reg[1:0] status;
reg[7:0] cmd_up;
reg[7:0] cmd_down;
reg[5:0] cnt;
always @(negedge clk or negedge reset)
begin
   if(!reset)
   begin
       status<=0;
       
   end
   else 
   begin
        case(status)
            'b00:
            begin
                if(|cmd_up)
                begin
                    status<='b11;
                end
                else if(|cmd_down)
                begin
                    status<='b01;
                end
                else 
                begin
                    status<='b00;
                end
            end
            'b01:
            begin
                if(|cmd_down)
                begin
                    status<='b01;
                end
                else
                begin 
                   status<='b00;
               end
            end
            'b11:
            begin
                if(|cmd_up)
                begin
                    status<='b11;
                end
                else 
                begin
                    status<='b00;
                end
            end
    endcase
   end
end


 always @(posedge clk or negedge reset )
   begin
  if(!reset)
	   begin
	   cmd_up <=0;
	   cmd_down <=0;
	   lastcmd<=0;
	   tempcmd<=0;
	   end
  else 
	if(cnt==CNT-2)
	     begin
		    if(status=='b01)
		       cmd_down[cfloor]<='b0;
		     else if(status=='b11)
		       cmd_up[cfloor]<='b0;
	     end
	else 
	if(load_enable)
	begin
	   if(cmd>cfloor )
         begin
              cmd_up[cmd]<='b1;
         end
      else if(cmd<cfloor)
         begin 
            cmd_down[cmd]<='b1;
         end
      else if(status=='b11)
       begin
           cmd_up[cmd]<='b1;
      end
      else 
      begin 
          cmd_down[cmd]<='b1;
      end
  end
  else if(lastcmd!=incmd)
	begin
    lastcmd<=incmd;      
	   if(incmd>cfloor )
         begin
              cmd_up[incmd]<='b1;
         end
      else if(incmd<cfloor)
         begin 
            cmd_down[incmd]<='b1;
         end
      else if(status=='b11)
       begin
           cmd_up[incmd]<='b1;
      end
      else 
      begin 
          cmd_down[incmd]<='b1;
      end
  end
  else lastcmd<=incmd;
       
 end
  

       
 always @(posedge clk or negedge reset)
    begin
	 if(!reset)
	 begin
	 	cnt<=0;
	 	cfloor<=0;
	 	CNT<=10;
	 end
	 else
        case(status)
            'b00:
            begin
                cnt<=0;
                CNT<=10;
            end
            'b01:
            begin
                if(cmd_down[cfloor]==1)
                  CNT<=20;
                 //else CNT<=10;
                if(cnt==CNT)
                begin
                    cnt<=0;
                    cfloor<=cfloor-1;
                    CNT<=10;
                end
                else 
                begin
                    cnt<=cnt+1;
                end
            end
            'b11:
            begin
                if(cmd_up[cfloor]==1)
                     CNT<=20;
                //else CNT<=10; 
                if(cnt==CNT)
                begin
                    cnt<=0;
                    cfloor<=cfloor+1;
                    CNT<=10;                                      
                end                          
                else
                begin
                    cnt<=cnt+1;
                end
            end
    endcase
        
end 

   
always @(posedge clk or negedge reset)
    begin
	 if(!reset)
	 begin
	 	open<=0;
	 end   
   else if(CNT==20&&cnt<=10&&cnt>2)
        open<='b1;
        else
        open<='b0;
   end   
 endmodule