Restore proper aspect ratio

Author: agg23

dist/Cores/agg23.NES/core.json

@@ -7,7 +7,7 @@
       "description": "Nintendo Entertainment System and Famicom. Nintendo's first home console",
       "author": "agg23",
       "url": "https://github.com/agg23/openFPGA-NES",
-      "version": "0.1.0",
+      "version": "0.1.1",
       "date_release": "2022-09-26"
     },
     "framework": {

dist/Cores/agg23.NES/video.json

@@ -5,8 +5,16 @@
       {
         "width": 256,
         "height": 240,
-        "aspect_w": 4,
-        "aspect_h": 3,
+        "aspect_w": 128,
+        "aspect_h": 105,
+        "rotation": 0,
+        "mirror": 0
+      },
+      {
+        "width": 256,
+        "height": 224,
+        "aspect_w": 64,
+        "aspect_h": 49,
         "rotation": 0,
         "mirror": 0
       }

src/fpga/apf/build_id.mif

@@ -10,7 +10,7 @@ CONTENT
 BEGIN
 
    0E0 : 20220926;
-   0E1 : 00070732;
-   0E2 : 4a64c356;
+   0E1 : 00130701;
+   0E2 : c4e2c76a;
 
 END;

src/fpga/core/core_top.v

@@ -709,9 +709,11 @@ module core_top (
   reg hs_prev;
   reg [2:0] hs_delay;
   reg vs_prev;
+  reg de_prev;
 
   wire de = ~(h_blank || v_blank);
   // TODO: Add PAL
+  wire [23:0] video_slot_rgb = {10'b0, hide_overscan, 10'b0, 3'b0};
 
   always @(posedge clk_video_5_37) begin
     video_hs_reg  <= 0;
@@ -722,6 +724,8 @@ module core_top (
       video_de_reg  <= 1;
 
       video_rgb_reg <= video_rgb_nes;
+    end else if (de_prev && ~de) begin
+      video_rgb_reg <= video_slot_rgb;
     end
 
     if (hs_delay > 0) begin
@@ -741,6 +745,7 @@ module core_top (
     video_vs_reg <= ~vs_prev && video_vs_nes;
     hs_prev <= video_hs_nes;
     vs_prev <= video_vs_nes;
+    de_prev <= de;
   end
 
   // Sound

src/fpga/core/rtl/video.sv

@@ -180,8 +180,13 @@ always @(posedge clk) begin
 	// number of 224 pixels, so we take off a proportional percentage from the sides to compensate.
 
 	if(pix_ce) begin
-		hblank <= (hc >= HBL_START) && (hc <= HBL_END);                // 280 pixels
-		vblank <= (vc >= VBL_START);                                   // 240 lines
+		if(hide_overscan) begin
+			hblank <= (hc >= HBL_START && hc <= HBL_END);                  // 280 - ((224/240) * 16) = 261.3
+			vblank <= (vc > (VBL_START - 9)) || (vc < 8);                  // 240 - 16 = 224
+		end else begin
+			hblank <= (hc >= HBL_START) && (hc <= HBL_END);                // 280 pixels
+			vblank <= (vc >= VBL_START);                                   // 240 lines
+		end
 
 		if(hc == 279) begin
 			HSync <= 1;
@@ -205,20 +210,12 @@ wire [7:0] ri = pixel[23:16];
 wire [7:0] gi = pixel[15:8];
 wire [7:0] bi = pixel[7:0];
 
-wire in_overscan = hide_overscan ? (vc <= VBL_START && vc > VBL_START - 9) || vc < 8 : 0;
-
 reg [7:0] ro,go,bo;
 always @(posedge clk) if (pix_ce_n) begin
 	reg [2:0] emph;
-	if (in_overscan) begin
-		ro <= 0;
-		go <= 0;
-		bo <= 0;
-	end else begin
-		ro <= ri;
-		go <= gi;
-		bo <= bi;
-	end
+	ro <= ri;
+	go <= gi;
+	bo <= bi;
 	emph <= 0;
 	if (~&color_ef[3:1]) begin // Only applies in draw range
 		emph <= emphasis;