Update sys.

sys/video_cleaner.sv

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+//
+//
+// Copyright (c) 2018 Sorgelig
+//
+// This program is GPL Licensed. See COPYING for the full license.
+//
+//
+////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+`timescale 1ns / 1ps
+
+module video_cleaner
+(
+	input            clk_vid,
+	input            ce_pix,
+
+	input      [7:0] R,
+	input      [7:0] G,
+	input      [7:0] B,
+
+	input            HSync,
+	input            VSync,
+	input            HBlank,
+	input            VBlank,
+
+	// video output signals
+	output reg [7:0] VGA_R,
+	output reg [7:0] VGA_G,
+	output reg [7:0] VGA_B,
+	output reg       VGA_VS,
+	output reg       VGA_HS,
+	output           VGA_DE,
+	
+	// optional aligned blank
+	output reg       HBlank_out,
+	output reg       VBlank_out
+);
+
+wire hs, vs;
+s_fix sync_v(clk_vid, HSync, hs);
+s_fix sync_h(clk_vid, VSync, vs);
+
+wire hbl = hs | HBlank;
+wire vbl = vs | VBlank;
+
+assign VGA_DE = ~(HBlank_out | VBlank_out);
+
+always @(posedge clk_vid) begin
+	if(ce_pix) begin
+		HBlank_out <= hbl;
+
+		VGA_VS <= vs;
+		VGA_HS <= hs;
+		VGA_R  <= R;
+		VGA_G  <= G;
+		VGA_B  <= B;
+
+		if(HBlank_out & ~hbl) VBlank_out <= vbl;
+	end
+end
+
+endmodule
+
+module s_fix
+(
+	input clk,
+	
+	input sync_in,
+	output sync_out
+);
+
+assign sync_out = sync_in ^ pol;
+
+reg pol;
+always @(posedge clk) begin
+	integer pos = 0, neg = 0, cnt = 0;
+	reg s1,s2;
+
+	s1 <= sync_in;
+	s2 <= s1;
+
+	if(~s2 & s1) neg <= cnt;
+	if(s2 & ~s1) pos <= cnt;
+
+	cnt <= cnt + 1;
+	if(s2 != s1) cnt <= 0;
+
+	pol <= pos > neg;
+end
+
+endmodule