/*
Written by Holguer A. Becerra
Based on Pong CHU VGA examples.
*/
module psp_screen_video_sync(clk, h_sync, v_sync, video_on, pixel_x, pixel_y);
parameter N=11;
input clk;
output h_sync, v_sync, video_on;
output [N-1:0] pixel_x;
output [N-1:0] pixel_y;

reg [N-1:0] counter_x;
reg [N-1:0] counter_y;

reg h_sync_reg;
reg v_sync_reg;

//parametros locales

localparam HD = 480; // horizontal display area
localparam HF = 2 ; // h. front (left) border
localparam HB = 2 ; // h. back (right) border
localparam HR = 41 ; // h. retrace
localparam VD = 272; // vertical display area
localparam VF = 2 ; // v. front (top) border
localparam VB = 2 ; // v. back (bottom) border
localparam VR = 10  ; // v. retrace


//contadores x & y

always @(posedge clk)
begin
     counter_y <= counter_y;
	  
	  if (counter_x >= (HD+HF+HB+HR-1))
	  begin
	       counter_x<=0;
			 if (counter_y >= (VD+VF+VB+VR-1))
			 begin
			 counter_y <= 0;
			 end
			 else
			 begin
			 counter_y <= counter_y + 1'b1;
			 end
	  end
	  else
	  begin
	  counter_x <= counter_x + 1'b1;
	  end

end


always @(posedge clk)
begin
     h_sync_reg <= (counter_x >= (HD+HB)) && (counter_x <= (HD+HB+HR-1));
	  v_sync_reg <= (counter_y >= (VD+VB)) && (counter_y <= (VD+VB+VR-1));
end

assign h_sync = h_sync_reg;
assign v_sync = v_sync_reg;
assign video_on = (counter_x < (HD)) && (counter_y < (VD));

assign pixel_x = counter_x;
assign pixel_y = counter_y;


endmodule