diff --git a/rtl/huc6270.sv b/rtl/huc6270.sv
index c3db4a2..234030c 100644
--- a/rtl/huc6270.sv
+++ b/rtl/huc6270.sv
@@ -277,7 +277,7 @@ reg SPR_FETCH_DONE;
 reg SPR_FETCH_W;
 reg [9:0] SPR_OUT_X;
 wire SPR_CE;
-wire [31:0] SPR_MAX;
+wire [6:0] SPR_MAX;
 reg [2:0] FETCH_DOT;
 reg FETCH_CE;
 wire [2:0] FDOT_CNT;
@@ -363,7 +363,7 @@ reg CLR_WE;
 
   assign FDOT_CNT = SP64 == 1'b0 ? DOT_CNT : FETCH_DOT;
   assign SPR_CE = SP64 == 1'b0 ? DCK_CE : FETCH_CE;
-  assign SPR_MAX = SP64 == 1'b0 ? 15 : 63;
+  assign SPR_MAX = SP64 == 1'b0 ? 7'd15 : 7'd63;
   assign HSW_END_POS = {2'b00,HSW} + ({6'b000000,RES7M});
   assign HDS_END_POS = ({2'b00,HSW}) + ({6'b000000,RES7M}) + 1 + (HDS);
   assign HDISP_END_POS = ({2'b00,HSW}) + ({6'b000000,RES7M}) + 1 + (HDS) + 1 + (HDW);
@@ -1055,10 +1055,6 @@ reg CLR_WE;
                   //else begin
                   //  SPR_CACHE[SPR_EVAL_CNT[5:0]].BOTTOM <= 1'b0;
                   //end
-                  //SPR_EVAL_CNT <= SPR_EVAL_CNT + 1;
-                  //if(SPR_EVAL_CNT == SPR_MAX) begin
-                  //  SPR_EVAL_FULL <= 1'b1;
-                  //end
                   Sprite_r spr_cache_rhs;
                   spr_cache_rhs.X = SPR_X;
                   spr_cache_rhs.Y = SPR_Y;
@@ -1074,6 +1070,11 @@ reg CLR_WE;
                   spr_cache_rhs.TOP = RC_CNT == SPR_Y;
                   spr_cache_rhs.BOTTOM = RC_CNT == (SPR_Y + 10'(SPR_H));
                   SPR_CACHE[SPR_EVAL_CNT[5:0]] <= spr_cache_rhs;
+
+                  SPR_EVAL_CNT <= SPR_EVAL_CNT + 1;
+                  if(SPR_EVAL_CNT == SPR_MAX) begin
+                    SPR_EVAL_FULL <= 1'b1;
+                  end
                 end
                 else begin
                   if(`CR_IE_OC == 1'b1) begin
diff --git a/rtl/tb/.gitignore b/rtl/tb/.gitignore
index 76c1c6c..158ac9d 100644
--- a/rtl/tb/.gitignore
+++ b/rtl/tb/.gitignore
@@ -1 +1,2 @@
 /rombios.bin
+/frames/
diff --git a/rtl/tb/mycore_tb.sv b/rtl/tb/mycore_tb.sv
index c772003..fd95811 100644
--- a/rtl/tb/mycore_tb.sv
+++ b/rtl/tb/mycore_tb.sv
@@ -7,6 +7,7 @@
 `timescale 1us / 1ns
 
 //`define USE_IOCTL_FOR_LOAD 1
+`define SAVE_FRAMES 1
 
 module mycore_tb;
 
@@ -50,6 +51,11 @@ reg [24:0]  ioctl_addr;
 reg [15:0]  ioctl_dout;
 wire        ioctl_wait;
 
+wire        pce;
+wire        hbl, vbl;
+wire        vs;
+wire [7:0]  r, g, b;
+
 mycore mycore
 (
 	.clk_sys(clk_sys),
@@ -79,16 +85,16 @@ mycore mycore
     .SDRAM_nRAS(SDRAM_nRAS),
     .SDRAM_nWE(SDRAM_nWE),
 
-	.ce_pix(),
+	.ce_pix(pce),
 
-	.HBlank(),
+	.HBlank(hbl),
 	.HSync(),
-	.VBlank(),
-	.VSync(),
+	.VBlank(vbl),
+	.VSync(vs),
 
-	.R(),
-	.G(),
-	.B()
+	.R(r),
+	.G(g),
+	.B(b)
 );
 
 initial begin
@@ -202,16 +208,68 @@ endtask
 
 //////////////////////////////////////////////////////////////////////
 
+`ifdef SAVE_FRAMES
+
+integer frame = 0;
+integer fpic;
+logic   pice;
+string  fname;
+
+initial fpic = -1;
+always @(negedge vs) begin
+  if (fpic != -1) begin
+    $fclose(fpic);
+    fpic = -1;
+`ifdef VERILATOR
+    $system({"python3 render2png.py ", fname, {".hex "}, fname, ".png; rm ", fname, ".hex"});
+`endif
+  end
+  $display("%t: Frame %03d", $time, frame);
+  $sformat(fname, "frames/render-%03d", frame);
+  pice = 0;
+  if ((frame % 1) == 0) begin
+    fpic = $fopen({fname, ".hex"}, "w");
+  end
+  frame = frame + 1;
+end
+final
+  $fclose(fpic);
+
+wire de = ~(hbl | vbl);
+
+always @(posedge clk_sys) begin
+  if (fpic != -1 && pce) begin
+    if (de) begin
+      $fwrite(fpic, "%x", {r, g, b});
+      pice = 1;
+    end
+    else if (pice) begin
+      pice = 0;
+      $fwrite(fpic, "\n");
+    end
+  end
+end
+
+`endif
+
+//////////////////////////////////////////////////////////////////////
+
 initial #0 begin
     #10 ; // wait for sdram init.
 
     load_rombios();
     $display("ROMs loaded.");
 
+    //load_file({4'h8, 21'h0}, "ram.bin", '0);
+
     reset = 0;
 end
 
 initial @(negedge reset) #(500e3) begin
+    //$writememh("vram0.hex", mycore.mach.vram0.mem);
+    //$writememh("vram1.hex", mycore.mach.vram1.mem);
+    //$writememh("vce_cp.hex", mycore.mach.vce.cpram.mem);
+
     $finish;
 end
 
diff --git a/rtl/tb/render2png.py b/rtl/tb/render2png.py
new file mode 100644
index 0000000..6d4ef31
--- /dev/null
+++ b/rtl/tb/render2png.py
@@ -0,0 +1,22 @@
+import sys
+import re
+from PIL import Image, ImageColor, ImageDraw
+
+img = Image.new('RGB', (256, 242))
+d = ImageDraw.Draw(img)
+
+with open(sys.argv[1], "r") as fin:
+    y = 0
+    for line in fin.readlines():
+        for x in range(len(line)//6):
+            w = line[x*6:x*6+6]
+            if not re.match(r'[0-9a-fA-F]{6}', w):
+                continue
+            r = int(w[0:2], 16)
+            g = int(w[2:4], 16)
+            b = int(w[4:6], 16)
+            c = (r,g,b)
+            d.point((x, y), fill=c)
+        y = y + 1
+
+img.save(sys.argv[2])