diff --git a/src/crab/gb/display.cr b/src/crab/gb/display.cr
index d0483fb..cc4ac31 100644
--- a/src/crab/gb/display.cr
+++ b/src/crab/gb/display.cr
@@ -5,8 +5,8 @@ module GB
     WIDTH  = 160
     HEIGHT = 144
 
-    PIXELFORMAT_RGB24       = (1 << 28) | (7 << 24) | (1 << 20) | (0 << 16) | (24 << 8) | (3 << 0)
-    TEXTUREACCESS_STREAMING = 1
+    PIXELFORMAT_BGR5        = 357764866
+    TEXTUREACCESS_STREAMING =         1
 
     @window : SDL::Window
     @renderer : SDL::Renderer
@@ -23,15 +23,15 @@ module GB
       @window = SDL::Window.new(window_title, WIDTH * DISPLAY_SCALE, HEIGHT * DISPLAY_SCALE, flags: flags)
       @renderer = SDL::Renderer.new @window
       @renderer.logical_size = {WIDTH, HEIGHT}
-      @texture = LibSDL.create_texture @renderer, PIXELFORMAT_RGB24, TEXTUREACCESS_STREAMING, WIDTH, HEIGHT
+      @texture = LibSDL.create_texture @renderer, PIXELFORMAT_BGR5, TEXTUREACCESS_STREAMING, WIDTH, HEIGHT
     end
 
     def window_title : String
       "CryBoy - #{@title} - #{@fps} fps"
     end
 
-    def draw(framebuffer : Array(RGB)) : Nil
-      LibSDL.update_texture @texture, nil, framebuffer, WIDTH * sizeof(RGB)
+    def draw(framebuffer : Slice(UInt16)) : Nil
+      LibSDL.update_texture @texture, nil, framebuffer, WIDTH * sizeof(UInt16)
       @renderer.clear
       @renderer.copy @texture
       @renderer.present
diff --git a/src/crab/gb/fifo_ppu.cr b/src/crab/gb/fifo_ppu.cr
index 2b9f2be..289fcd5 100644
--- a/src/crab/gb/fifo_ppu.cr
+++ b/src/crab/gb/fifo_ppu.cr
@@ -196,14 +196,14 @@ module GB
           if !sprite_pixel.nil? && sprite_wins? bg_pixel, sprite_pixel
             pixel = sprite_pixel
             palette = sprite_pixel.palette == 0 ? @obp0 : @obp1
-            palettes = @obj_palettes
+            arr = @obj_pram
           else
             pixel = bg_pixel
             palette = @bgp
-            palettes = @palettes
+            arr = @pram
           end
           color = @cgb_ptr.value ? pixel.color : palette[pixel.color]
-          @framebuffer[Display::WIDTH * @ly + @lx] = palettes[pixel.palette][color]
+          @framebuffer[Display::WIDTH * @ly + @lx] = arr.to_unsafe.as(UInt16*)[4 * pixel.palette + color]
         end
         @lx += 1
         if @lx == Display::WIDTH
diff --git a/src/crab/gb/ppu.cr b/src/crab/gb/ppu.cr
index 955d9dd..a1747f2 100644
--- a/src/crab/gb/ppu.cr
+++ b/src/crab/gb/ppu.cr
@@ -1,469 +1,403 @@
-  # This file is simply designed to hold shared features of the scanline and FIFO
-  # renderers while the FIFO renderer is in active development. The purpose of
-  # this file is solely to reduce common changes to both renderers.
+# This file is simply designed to hold shared features of the scanline and FIFO
+# renderers while the FIFO renderer is in active development. The purpose of
+# this file is solely to reduce common changes to both renderers.
 
-  module GB
-    struct Sprite
-      getter oam_idx : UInt8 = 0_u8
+module GB
+  struct Sprite
+    getter oam_idx : UInt8 = 0_u8
 
-      def initialize(@y : UInt8, @x : UInt8, @tile_num : UInt8, @attributes : UInt8)
-      end
+    def initialize(@y : UInt8, @x : UInt8, @tile_num : UInt8, @attributes : UInt8)
+    end
 
-      def initialize(oam : Bytes, @oam_idx : UInt8)
-        initialize oam[oam_idx], oam[oam_idx + 1], oam[oam_idx + 2], oam[oam_idx + 3]
-      end
+    def initialize(oam : Bytes, @oam_idx : UInt8)
+      initialize oam[oam_idx], oam[oam_idx + 1], oam[oam_idx + 2], oam[oam_idx + 3]
+    end
 
-      def to_s(io : IO)
-        io << "Sprite(y:#{@y}, x:#{@x}, tile_num:#{@tile_num}, tile_ptr: #{hex_str tile_ptr}, visible:#{visible?}, priority:#{priority}, y_flip:#{y_flip?}, x_flip:#{x_flip?}, dmg_palette_number:#{dmg_palette_numpalette_number}"
-      end
+    def to_s(io : IO)
+      io << "Sprite(y:#{@y}, x:#{@x}, tile_num:#{@tile_num}, tile_ptr: #{hex_str tile_ptr}, visible:#{visible?}, priority:#{priority}, y_flip:#{y_flip?}, x_flip:#{x_flip?}, dmg_palette_number:#{dmg_palette_numpalette_number}"
+    end
 
-      def on_line(line : Int, sprite_height = 8) : Bool
-        y <= line + 16 < y + sprite_height
-      end
+    def on_line(line : Int, sprite_height = 8) : Bool
+      y <= line + 16 < y + sprite_height
+    end
 
-      # behavior is undefined if sprite is not on given line
-      def bytes(line : Int, sprite_height = 8) : Tuple(UInt16, UInt16)
-        actual_y = -16 + y
-        if sprite_height == 8
-          tile_ptr = 16_u16 * @tile_num
-        else # 8x16 tile
-          if (actual_y + 8 <= line) ^ y_flip?
-            tile_ptr = 16_u16 * (@tile_num | 0x01)
-          else
-            tile_ptr = 16_u16 * (@tile_num & 0xFE)
-          end
-        end
-        sprite_row = (line.to_i16 - actual_y) & 7
-        if y_flip?
-          {tile_ptr + (7 - sprite_row) * 2, tile_ptr + (7 - sprite_row) * 2 + 1}
+    # behavior is undefined if sprite is not on given line
+    def bytes(line : Int, sprite_height = 8) : Tuple(UInt16, UInt16)
+      actual_y = -16 + y
+      if sprite_height == 8
+        tile_ptr = 16_u16 * @tile_num
+      else # 8x16 tile
+        if (actual_y + 8 <= line) ^ y_flip?
+          tile_ptr = 16_u16 * (@tile_num | 0x01)
         else
-          {tile_ptr + sprite_row * 2, tile_ptr + sprite_row * 2 + 1}
+          tile_ptr = 16_u16 * (@tile_num & 0xFE)
         end
       end
-
-      def visible? : Bool
-        ((1...160).includes? y) && ((1...168).includes? x)
-      end
-
-      def y : UInt8
-        @y
-      end
-
-      def x : UInt8
-        @x
-      end
-
-      def priority : UInt8
-        (@attributes >> 7) & 0x1
-      end
-
-      def y_flip? : Bool
-        (@attributes >> 6) & 0x1 == 1
-      end
-
-      def x_flip? : Bool
-        (@attributes >> 5) & 0x1 == 1
-      end
-
-      def dmg_palette_number : UInt8
-        (@attributes >> 4) & 0x1
-      end
-
-      def bank_num : UInt8
-        (@attributes >> 3) & 0x1
-      end
-
-      def cgb_palette_number : UInt8
-        @attributes & 0b111
+      sprite_row = (line.to_i16 - actual_y) & 7
+      if y_flip?
+        {tile_ptr + (7 - sprite_row) * 2, tile_ptr + (7 - sprite_row) * 2 + 1}
+      else
+        {tile_ptr + sprite_row * 2, tile_ptr + sprite_row * 2 + 1}
       end
     end
 
-    struct RGB
-      property red, green, blue
-
-      def initialize(@red : UInt8, @green : UInt8, @blue : UInt8)
-      end
-
-      def initialize(grey : UInt8)
-        @red = @green = @blue = grey
-      end
-
-      def self.from_bgr16(bgr : UInt16, should_convert : Bool) : RGB
-        color = RGB.new(
-          0x1F_u8 & bgr,
-          0x1F_u8 & (bgr >> 5),
-          0x1F_u8 & (bgr >> 10)
-        )
-        should_convert ? color.convert_from_cgb : color
-      end
-
-      def convert_from_cgb : RGB
-        {% unless flag? :graphics_test %}
-          # correction algorithm from: https://byuu.net/video/color-emulation
-          RGB.new(
-            Math.min(240, (26_u32 * @red + 4_u32 * @green + 2_u32 * @blue) >> 2).to_u8,
-            Math.min(240, (24_u32 * @green + 8_u32 * @blue) >> 2).to_u8,
-            Math.min(240, (6_u32 * @red + 4_u32 * @green + 22_u32 * @blue) >> 2).to_u8
-          )
-        {% else %}
-          # documented in https://github.com/mattcurrie/mealybug-tearoom-tests
-          RGB.new(
-            @red << 3 | @red >> 2,
-            @green << 3 | @green >> 2,
-            @blue << 3 | @blue >> 2
-          )
-        {% end %}
-      end
+    def visible? : Bool
+      ((1...160).includes? y) && ((1...168).includes? x)
     end
 
-    POST_BOOT_VRAM = [
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-      0xF0, 0x00, 0xF0, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xF3, 0x00, 0xF3, 0x00,
-      0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00,
-      0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF3, 0x00, 0xF3, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xCF, 0x00, 0xCF, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x0F, 0x00, 0x0F, 0x00, 0x3F, 0x00, 0x3F, 0x00, 0x0F, 0x00, 0x0F, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xC0, 0x00, 0xC0, 0x00, 0x0F, 0x00, 0x0F, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0x00, 0xF0, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF3, 0x00, 0xF3, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xC0, 0x00, 0xC0, 0x00,
-      0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0xFF, 0x00, 0xFF, 0x00,
-      0xC0, 0x00, 0xC0, 0x00, 0xC0, 0x00, 0xC0, 0x00, 0xC0, 0x00, 0xC0, 0x00, 0xC3, 0x00, 0xC3, 0x00,
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFC, 0x00, 0xFC, 0x00,
-      0xF3, 0x00, 0xF3, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00,
-      0x3C, 0x00, 0x3C, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0x3C, 0x00, 0x3C, 0x00,
-      0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00,
-      0xF3, 0x00, 0xF3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00,
-      0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00,
-      0x3C, 0x00, 0x3C, 0x00, 0x3F, 0x00, 0x3F, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x0F, 0x00, 0x0F, 0x00,
-      0x3C, 0x00, 0x3C, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFC, 0x00, 0xFC, 0x00,
-      0xFC, 0x00, 0xFC, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00,
-      0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF0, 0x00, 0xF0, 0x00,
-      0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xFF, 0x00, 0xFF, 0x00,
-      0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xC3, 0x00, 0xC3, 0x00,
-      0x0F, 0x00, 0x0F, 0x00, 0x0F, 0x00, 0x0F, 0x00, 0x0F, 0x00, 0x0F, 0x00, 0xFC, 0x00, 0xFC, 0x00,
-      0x3C, 0x00, 0x42, 0x00, 0xB9, 0x00, 0xA5, 0x00, 0xB9, 0x00, 0xA5, 0x00, 0x42, 0x00, 0x3C, 0x00,
-    ]
+    def y : UInt8
+      @y
+    end
 
-    abstract class PPU
-      @ran_bios : Bool # determine if colors should be adjusted for cgb
-      @cgb_ptr : Pointer(Bool)
+    def x : UInt8
+      @x
+    end
 
-      @framebuffer = Array(RGB).new Display::WIDTH * Display::HEIGHT, RGB.new(0, 0, 0)
+    def priority : UInt8
+      (@attributes >> 7) & 0x1
+    end
 
-      @pram = Bytes.new 64
-      @palettes = Array(Array(RGB)).new 8 { Array(GB::RGB).new 4, GB::RGB.new(0, 0, 0) }
-      @palette_index : UInt8 = 0
-      @auto_increment = false
+    def y_flip? : Bool
+      (@attributes >> 6) & 0x1 == 1
+    end
 
-      @obj_pram = Bytes.new 64
-      @obj_palettes = Array(Array(RGB)).new 8 { Array(GB::RGB).new 4, GB::RGB.new(0, 0, 0) }
-      @obj_palette_index : UInt8 = 0
-      @obj_auto_increment = false
+    def x_flip? : Bool
+      (@attributes >> 5) & 0x1 == 1
+    end
 
-      @vram = Array(Bytes).new 2 { Bytes.new GB::Memory::VRAM.size } # 0x8000..0x9FFF
-      @vram_bank : UInt8 = 0                                         # track which bank is active
-      @sprite_table = Bytes.new Memory::OAM.size                     # 0xFE00..0xFE9F
-      @lcd_control : UInt8 = 0x00_u8                                 # 0xFF40
-      @lcd_status : UInt8 = 0x80_u8                                  # 0xFF41
-      @scy : UInt8 = 0x00_u8                                         # 0xFF42
-      @scx : UInt8 = 0x00_u8                                         # 0xFF43
-      @ly : UInt8 = 0x00_u8                                          # 0xFF44
-      @lyc : UInt8 = 0x00_u8                                         # 0xFF45
-      @dma : UInt8 = 0x00_u8                                         # 0xFF46
-      @bgp : Array(UInt8) = Array(UInt8).new 4, 0                    # 0xFF47
-      @obp0 : Array(UInt8) = Array(UInt8).new 4, 0                   # 0xFF48
-      @obp1 : Array(UInt8) = Array(UInt8).new 4, 0                   # 0xFF49
-      @wy : UInt8 = 0x00_u8                                          # 0xFF4A
-      @wx : UInt8 = 0x00_u8                                          # 0xFF4B
+    def dmg_palette_number : UInt8
+      (@attributes >> 4) & 0x1
+    end
 
-      # At some point, wy _must_ equal ly to enable the window
-      @window_trigger = false
-      @current_window_line = 0
+    def bank_num : UInt8
+      (@attributes >> 3) & 0x1
+    end
 
-      @old_stat_flag = false
-
-      @hdma1 : UInt8 = 0xFF
-      @hdma2 : UInt8 = 0xFF
-      @hdma3 : UInt8 = 0xFF
-      @hdma4 : UInt8 = 0xFF
-      @hdma5 : UInt8 = 0xFF
-      @hdma_src : UInt16 = 0x0000
-      @hdma_dst : UInt16 = 0x8000
-      @hdma_pos : UInt16 = 0x0000
-      @hdma_active : Bool = false
-
-      @first_line = true
-
-      # count number of cycles into current line on fifo, or the number of cycles into the current mode on scanline
-      @cycle_counter : Int32 = 0
-
-      def initialize(@gb : GB)
-        @cgb_ptr = gb.cgb_ptr
-        unless @cgb_ptr.value # fill default color palettes
-          {% if flag? :pink %}
-            @palettes[0] = @obj_palettes[0] = @obj_palettes[1] = [
-              RGB.new(0xFF, 0xF6, 0xD3), RGB.new(0xF9, 0xA8, 0x75),
-              RGB.new(0xEB, 0x6B, 0x6F), RGB.new(0x7C, 0x3F, 0x58),
-            ]
-          {% elsif flag? :graphics_test %}
-            @palettes[0] = @obj_palettes[0] = @obj_palettes[1] = [
-              RGB.new(0xFF, 0xFF, 0xFF), RGB.new(0xAA, 0xAA, 0xAA),
-              RGB.new(0x55, 0x55, 0x55), RGB.new(0x00, 0x00, 0x00),
-            ]
-          {% else %}
-            @palettes[0] = @obj_palettes[0] = @obj_palettes[1] = [
-              RGB.new(0xE0, 0xF8, 0xCF), RGB.new(0x86, 0xC0, 0x6C),
-              RGB.new(0x30, 0x68, 0x50), RGB.new(0x07, 0x17, 0x20),
-            ]
-          {% end %}
-        end
-        @ran_bios = @cgb_ptr.value
-      end
-
-      def skip_boot : Nil
-        POST_BOOT_VRAM.each_with_index do |byte, idx|
-          @vram[0][idx] = byte.to_u8
-        end
-      end
-
-      # handle stat interrupts
-      # stat interrupts are only requested on the rising edge
-      def handle_stat_interrupt : Nil
-        self.coincidence_flag = @ly == @lyc
-        stat_flag = (coincidence_flag && coincidence_interrupt_enabled) ||
-                    (mode_flag == 2 && oam_interrupt_enabled) ||
-                    (mode_flag == 0 && hblank_interrupt_enabled) ||
-                    (mode_flag == 1 && vblank_interrupt_enabled)
-        if !@old_stat_flag && stat_flag
-          @gb.interrupts.lcd_stat_interrupt = true
-        end
-        @old_stat_flag = stat_flag
-      end
-
-      # Copy 16-byte block from hdma_src to hdma_dst, then decrement value in hdma5
-      def copy_hdma_block(block_number : Int) : Nil
-        0x10.times do |byte|
-          offset = 0x10 * block_number + byte
-          @gb.memory.write_byte @hdma_dst &+ offset, @gb.memory.read_byte @hdma_src &+ offset
-          @gb.memory.tick_components 2, from_cpu: false, ignore_speed: true
-        end
-        @hdma5 &-= 1
-      end
-
-      def start_hdma(value : UInt8) : Nil
-        @hdma_src = ((@hdma1.to_u16 << 8) | @hdma2) & 0xFFF0
-        @hdma_dst = 0x8000_u16 + (((@hdma3.to_u16 << 8) | @hdma4) & 0x1FF0)
-        @hdma5 = value & 0x7F
-        if value & 0x80 > 0 # hdma
-          @hdma_active = true
-          @hdma_pos = 0
-        else # gdma
-          unless @hdma_active
-            (@hdma5 + 1).times do |block_num|
-              copy_hdma_block block_num
-            end
-          end
-          @hdma_active = false
-        end
-      end
-
-      def step_hdma : Nil
-        copy_hdma_block @hdma_pos
-        @hdma_pos += 1
-        @hdma_active = false if @hdma5 == 0xFF
-      end
-
-      # read from ppu memory
-      def [](index : Int) : UInt8
-        case index
-        when Memory::VRAM then @vram[@vram_bank][index - Memory::VRAM.begin]
-        when Memory::OAM  then @sprite_table[index - Memory::OAM.begin]
-        when 0xFF40       then @lcd_control
-        when 0xFF41
-          if @first_line && mode_flag == 2
-            @lcd_status & 0b11111100
-          else
-            @lcd_status
-          end
-        when 0xFF42 then @scy
-        when 0xFF43 then @scx
-        when 0xFF44 then @ly
-        when 0xFF45 then @lyc
-        when 0xFF46 then @dma
-        when 0xFF47 then palette_from_array @bgp
-        when 0xFF48 then palette_from_array @obp0
-        when 0xFF49 then palette_from_array @obp1
-        when 0xFF4A then @wy
-        when 0xFF4B then @wx
-        when 0xFF4F then @cgb_ptr.value ? 0xFE_u8 | @vram_bank : 0xFF_u8
-        when 0xFF51 then @cgb_ptr.value ? @hdma1 : 0xFF_u8
-        when 0xFF52 then @cgb_ptr.value ? @hdma2 : 0xFF_u8
-        when 0xFF53 then @cgb_ptr.value ? @hdma3 : 0xFF_u8
-        when 0xFF54 then @cgb_ptr.value ? @hdma4 : 0xFF_u8
-        when 0xFF55 then @cgb_ptr.value ? @hdma5 : 0xFF_u8
-        when 0xFF68 then @cgb_ptr.value ? 0x40_u8 | (@auto_increment ? 0x80 : 0) | @palette_index : 0xFF_u8
-        when 0xFF69 then @cgb_ptr.value ? @pram[@palette_index] : 0xFF_u8
-        when 0xFF6A then @cgb_ptr.value ? 0x40_u8 | (@obj_auto_increment ? 0x80 : 0) | @obj_palette_index : 0xFF_u8
-        when 0xFF6B then @cgb_ptr.value ? @obj_pram[@obj_palette_index] : 0xFF_u8
-        else             raise "Reading from invalid ppu register: #{hex_str index.to_u16!}"
-        end
-      end
-
-      # write to ppu memory
-      def []=(index : Int, value : UInt8) : Nil
-        case index
-        when Memory::VRAM then @vram[@vram_bank][index - Memory::VRAM.begin] = value
-        when Memory::OAM  then @sprite_table[index - Memory::OAM.begin] = value
-        when 0xFF40
-          if value & 0x80 > 0 && !lcd_enabled?
-            @ly = 0
-            self.mode_flag = 2
-            @first_line = true
-          end
-          @lcd_control = value
-          handle_stat_interrupt
-        when 0xFF41
-          @lcd_status = (@lcd_status & 0b10000111) | (value & 0b01111000)
-          handle_stat_interrupt
-        when 0xFF42 then @scy = value
-        when 0xFF43 then @scx = value
-        when 0xFF44 then nil # read only
-        when 0xFF45
-          @lyc = value
-          handle_stat_interrupt
-        when 0xFF46 then @dma = value
-        when 0xFF47 then @bgp = palette_to_array value
-        when 0xFF48 then @obp0 = palette_to_array value
-        when 0xFF49 then @obp1 = palette_to_array value
-        when 0xFF4A then @wy = value
-        when 0xFF4B then @wx = value
-        when 0xFF4F then @vram_bank = value & 1 if @cgb_ptr.value
-        when 0xFF51 then @hdma1 = value if @cgb_ptr.value
-        when 0xFF52 then @hdma2 = value if @cgb_ptr.value
-        when 0xFF53 then @hdma3 = value if @cgb_ptr.value
-        when 0xFF54 then @hdma4 = value if @cgb_ptr.value
-        when 0xFF55 then start_hdma value if @cgb_ptr.value
-        when 0xFF68
-          if @cgb_ptr.value
-            @palette_index = value & 0x3F
-            @auto_increment = value & 0x80 > 0
-          end
-        when 0xFF69
-          if @cgb_ptr.value
-            @pram[@palette_index] = value
-            bgr16 = @pram[@palette_index | 1].to_u16 << 8 | @pram[@palette_index & ~1]
-            palette_number = @palette_index >> 3
-            color_number = (@palette_index & 7) >> 1
-            @palettes[palette_number][color_number] = RGB.from_bgr16 bgr16, @ran_bios
-            @palette_index += 1 if @auto_increment
-            @palette_index &= 0x3F
-          end
-        when 0xFF6A
-          if @cgb_ptr.value
-            @obj_palette_index = value & 0x3F
-            @obj_auto_increment = value & 0x80 > 0
-          end
-        when 0xFF6B
-          if @cgb_ptr.value
-            @obj_pram[@obj_palette_index] = value
-            bgr16 = @obj_pram[@obj_palette_index | 1].to_u16 << 8 | @obj_pram[@obj_palette_index & ~1]
-            palette_number = @obj_palette_index >> 3
-            color_number = (@obj_palette_index & 7) >> 1
-            @obj_palettes[palette_number][color_number] = RGB.from_bgr16 bgr16, @ran_bios
-            @obj_palette_index += 1 if @obj_auto_increment
-            @obj_palette_index &= 0x3F
-          end
-        else raise "Writing to invalid ppu register: #{hex_str index.to_u16!}"
-        end
-      end
-
-      # LCD Control Register
-
-      def lcd_enabled? : Bool
-        @lcd_control & (0x1 << 7) != 0
-      end
-
-      def window_tile_map : UInt8
-        @lcd_control & (0x1 << 6)
-      end
-
-      def window_enabled? : Bool
-        @lcd_control & (0x1 << 5) != 0
-      end
-
-      def bg_window_tile_data : UInt8
-        @lcd_control & (0x1 << 4)
-      end
-
-      def bg_tile_map : UInt8
-        @lcd_control & (0x1 << 3)
-      end
-
-      def sprite_height
-        @lcd_control & (0x1 << 2) != 0 ? 16 : 8
-      end
-
-      def sprite_enabled? : Bool
-        @lcd_control & (0x1 << 1) != 0
-      end
-
-      def bg_display? : Bool
-        @lcd_control & 0x1 != 0
-      end
-
-      # LCD Status Register
-
-      def coincidence_interrupt_enabled : Bool
-        @lcd_status & (0x1 << 6) != 0
-      end
-
-      def oam_interrupt_enabled : Bool
-        @lcd_status & (0x1 << 5) != 0
-      end
-
-      def vblank_interrupt_enabled : Bool
-        @lcd_status & (0x1 << 4) != 0
-      end
-
-      def hblank_interrupt_enabled : Bool
-        @lcd_status & (0x1 << 3) != 0
-      end
-
-      def coincidence_flag : Bool
-        @lcd_status & (0x1 << 2) != 0
-      end
-
-      def coincidence_flag=(on : Bool) : Nil
-        @lcd_status = (@lcd_status & ~(0x1 << 2)) | (on ? (0x1 << 2) : 0)
-      end
-
-      def mode_flag : UInt8
-        @lcd_status & 0x3
-      end
-
-      def mode_flag=(mode : UInt8)
-        step_hdma if mode == 0 && @hdma_active
-        @first_line = false if @first_line && mode_flag == 0 && mode == 2
-        @window_trigger = false if mode == 1
-        @lcd_status = (@lcd_status & 0b11111100) | mode
-        handle_stat_interrupt
-      end
-
-      # palettes
-
-      def palette_to_array(palette : UInt8) : Array(UInt8)
-        [palette & 0x3, (palette >> 2) & 0x3, (palette >> 4) & 0x3, (palette >> 6) & 0x3]
-      end
-
-      def palette_from_array(palette_array : Array(UInt8)) : UInt8
-        palette_array.each_with_index.reduce(0x00_u8) do |palette, (color, idx)|
-          palette | color << (idx * 2)
-        end
-      end
-
-      def write_png : Nil
-        @gb.display.write_png @framebuffer
-      end
+    def cgb_palette_number : UInt8
+      @attributes & 0b111
     end
   end
+
+  POST_BOOT_VRAM = [
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0xF0, 0x00, 0xF0, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xF3, 0x00, 0xF3, 0x00,
+    0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x3C, 0x00,
+    0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF3, 0x00, 0xF3, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xCF, 0x00, 0xCF, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x0F, 0x00, 0x0F, 0x00, 0x3F, 0x00, 0x3F, 0x00, 0x0F, 0x00, 0x0F, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xC0, 0x00, 0xC0, 0x00, 0x0F, 0x00, 0x0F, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0x00, 0xF0, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF3, 0x00, 0xF3, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xC0, 0x00, 0xC0, 0x00,
+    0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0xFF, 0x00, 0xFF, 0x00,
+    0xC0, 0x00, 0xC0, 0x00, 0xC0, 0x00, 0xC0, 0x00, 0xC0, 0x00, 0xC0, 0x00, 0xC3, 0x00, 0xC3, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFC, 0x00, 0xFC, 0x00,
+    0xF3, 0x00, 0xF3, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00,
+    0x3C, 0x00, 0x3C, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0x3C, 0x00, 0x3C, 0x00,
+    0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00,
+    0xF3, 0x00, 0xF3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00,
+    0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00,
+    0x3C, 0x00, 0x3C, 0x00, 0x3F, 0x00, 0x3F, 0x00, 0x3C, 0x00, 0x3C, 0x00, 0x0F, 0x00, 0x0F, 0x00,
+    0x3C, 0x00, 0x3C, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFC, 0x00, 0xFC, 0x00,
+    0xFC, 0x00, 0xFC, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00, 0xF0, 0x00,
+    0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF3, 0x00, 0xF0, 0x00, 0xF0, 0x00,
+    0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xC3, 0x00, 0xFF, 0x00, 0xFF, 0x00,
+    0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xCF, 0x00, 0xC3, 0x00, 0xC3, 0x00,
+    0x0F, 0x00, 0x0F, 0x00, 0x0F, 0x00, 0x0F, 0x00, 0x0F, 0x00, 0x0F, 0x00, 0xFC, 0x00, 0xFC, 0x00,
+    0x3C, 0x00, 0x42, 0x00, 0xB9, 0x00, 0xA5, 0x00, 0xB9, 0x00, 0xA5, 0x00, 0x42, 0x00, 0x3C, 0x00,
+  ]
+
+  abstract class PPU
+    @ran_bios : Bool # determine if colors should be adjusted for cgb
+    @cgb_ptr : Pointer(Bool)
+
+    @framebuffer = Slice(UInt16).new Display::WIDTH * Display::HEIGHT
+
+    @pram = Bytes.new 64
+    @palette_index : UInt8 = 0
+    @auto_increment = false
+
+    @obj_pram = Bytes.new 64
+    @obj_palette_index : UInt8 = 0
+    @obj_auto_increment = false
+
+    @vram = Array(Bytes).new 2 { Bytes.new GB::Memory::VRAM.size } # 0x8000..0x9FFF
+    @vram_bank : UInt8 = 0                                         # track which bank is active
+    @sprite_table = Bytes.new Memory::OAM.size                     # 0xFE00..0xFE9F
+    @lcd_control : UInt8 = 0x00_u8                                 # 0xFF40
+    @lcd_status : UInt8 = 0x80_u8                                  # 0xFF41
+    @scy : UInt8 = 0x00_u8                                         # 0xFF42
+    @scx : UInt8 = 0x00_u8                                         # 0xFF43
+    @ly : UInt8 = 0x00_u8                                          # 0xFF44
+    @lyc : UInt8 = 0x00_u8                                         # 0xFF45
+    @dma : UInt8 = 0x00_u8                                         # 0xFF46
+    @bgp : Array(UInt8) = Array(UInt8).new 4, 0                    # 0xFF47
+    @obp0 : Array(UInt8) = Array(UInt8).new 4, 0                   # 0xFF48
+    @obp1 : Array(UInt8) = Array(UInt8).new 4, 0                   # 0xFF49
+    @wy : UInt8 = 0x00_u8                                          # 0xFF4A
+    @wx : UInt8 = 0x00_u8                                          # 0xFF4B
+
+    # At some point, wy _must_ equal ly to enable the window
+    @window_trigger = false
+    @current_window_line = 0
+
+    @old_stat_flag = false
+
+    @hdma1 : UInt8 = 0xFF
+    @hdma2 : UInt8 = 0xFF
+    @hdma3 : UInt8 = 0xFF
+    @hdma4 : UInt8 = 0xFF
+    @hdma5 : UInt8 = 0xFF
+    @hdma_src : UInt16 = 0x0000
+    @hdma_dst : UInt16 = 0x8000
+    @hdma_pos : UInt16 = 0x0000
+    @hdma_active : Bool = false
+
+    @first_line = true
+
+    # count number of cycles into current line on fifo, or the number of cycles into the current mode on scanline
+    @cycle_counter : Int32 = 0
+
+    def initialize(@gb : GB)
+      @cgb_ptr = gb.cgb_ptr
+      @ran_bios = @cgb_ptr.value
+    end
+
+    def skip_boot : Nil
+      POST_BOOT_VRAM.each_with_index do |byte, idx|
+        @vram[0][idx] = byte.to_u8
+      end
+    end
+
+    # handle stat interrupts
+    # stat interrupts are only requested on the rising edge
+    def handle_stat_interrupt : Nil
+      self.coincidence_flag = @ly == @lyc
+      stat_flag = (coincidence_flag && coincidence_interrupt_enabled) ||
+                  (mode_flag == 2 && oam_interrupt_enabled) ||
+                  (mode_flag == 0 && hblank_interrupt_enabled) ||
+                  (mode_flag == 1 && vblank_interrupt_enabled)
+      if !@old_stat_flag && stat_flag
+        @gb.interrupts.lcd_stat_interrupt = true
+      end
+      @old_stat_flag = stat_flag
+    end
+
+    # Copy 16-byte block from hdma_src to hdma_dst, then decrement value in hdma5
+    def copy_hdma_block(block_number : Int) : Nil
+      0x10.times do |byte|
+        offset = 0x10 * block_number + byte
+        @gb.memory.write_byte @hdma_dst &+ offset, @gb.memory.read_byte @hdma_src &+ offset
+        @gb.memory.tick_components 2, from_cpu: false, ignore_speed: true
+      end
+      @hdma5 &-= 1
+    end
+
+    def start_hdma(value : UInt8) : Nil
+      @hdma_src = ((@hdma1.to_u16 << 8) | @hdma2) & 0xFFF0
+      @hdma_dst = 0x8000_u16 + (((@hdma3.to_u16 << 8) | @hdma4) & 0x1FF0)
+      @hdma5 = value & 0x7F
+      if value & 0x80 > 0 # hdma
+        @hdma_active = true
+        @hdma_pos = 0
+      else # gdma
+        unless @hdma_active
+          (@hdma5 + 1).times do |block_num|
+            copy_hdma_block block_num
+          end
+        end
+        @hdma_active = false
+      end
+    end
+
+    def step_hdma : Nil
+      copy_hdma_block @hdma_pos
+      @hdma_pos += 1
+      @hdma_active = false if @hdma5 == 0xFF
+    end
+
+    # read from ppu memory
+    def [](index : Int) : UInt8
+      case index
+      when Memory::VRAM then @vram[@vram_bank][index - Memory::VRAM.begin]
+      when Memory::OAM  then @sprite_table[index - Memory::OAM.begin]
+      when 0xFF40       then @lcd_control
+      when 0xFF41
+        if @first_line && mode_flag == 2
+          @lcd_status & 0b11111100
+        else
+          @lcd_status
+        end
+      when 0xFF42 then @scy
+      when 0xFF43 then @scx
+      when 0xFF44 then @ly
+      when 0xFF45 then @lyc
+      when 0xFF46 then @dma
+      when 0xFF47 then palette_from_array @bgp
+      when 0xFF48 then palette_from_array @obp0
+      when 0xFF49 then palette_from_array @obp1
+      when 0xFF4A then @wy
+      when 0xFF4B then @wx
+      when 0xFF4F then @cgb_ptr.value ? 0xFE_u8 | @vram_bank : 0xFF_u8
+      when 0xFF51 then @cgb_ptr.value ? @hdma1 : 0xFF_u8
+      when 0xFF52 then @cgb_ptr.value ? @hdma2 : 0xFF_u8
+      when 0xFF53 then @cgb_ptr.value ? @hdma3 : 0xFF_u8
+      when 0xFF54 then @cgb_ptr.value ? @hdma4 : 0xFF_u8
+      when 0xFF55 then @cgb_ptr.value ? @hdma5 : 0xFF_u8
+      when 0xFF68 then @cgb_ptr.value ? 0x40_u8 | (@auto_increment ? 0x80 : 0) | @palette_index : 0xFF_u8
+      when 0xFF69 then @cgb_ptr.value ? @pram[@palette_index] : 0xFF_u8
+      when 0xFF6A then @cgb_ptr.value ? 0x40_u8 | (@obj_auto_increment ? 0x80 : 0) | @obj_palette_index : 0xFF_u8
+      when 0xFF6B then @cgb_ptr.value ? @obj_pram[@obj_palette_index] : 0xFF_u8
+      else             raise "Reading from invalid ppu register: #{hex_str index.to_u16!}"
+      end
+    end
+
+    # write to ppu memory
+    def []=(index : Int, value : UInt8) : Nil
+      case index
+      when Memory::VRAM then @vram[@vram_bank][index - Memory::VRAM.begin] = value
+      when Memory::OAM  then @sprite_table[index - Memory::OAM.begin] = value
+      when 0xFF40
+        if value & 0x80 > 0 && !lcd_enabled?
+          @ly = 0
+          self.mode_flag = 2
+          @first_line = true
+        end
+        @lcd_control = value
+        handle_stat_interrupt
+      when 0xFF41
+        @lcd_status = (@lcd_status & 0b10000111) | (value & 0b01111000)
+        handle_stat_interrupt
+      when 0xFF42 then @scy = value
+      when 0xFF43 then @scx = value
+      when 0xFF44 then nil # read only
+      when 0xFF45
+        @lyc = value
+        handle_stat_interrupt
+      when 0xFF46 then @dma = value
+      when 0xFF47 then @bgp = palette_to_array value
+      when 0xFF48 then @obp0 = palette_to_array value
+      when 0xFF49 then @obp1 = palette_to_array value
+      when 0xFF4A then @wy = value
+      when 0xFF4B then @wx = value
+      when 0xFF4F then @vram_bank = value & 1 if @cgb_ptr.value
+      when 0xFF51 then @hdma1 = value if @cgb_ptr.value
+      when 0xFF52 then @hdma2 = value if @cgb_ptr.value
+      when 0xFF53 then @hdma3 = value if @cgb_ptr.value
+      when 0xFF54 then @hdma4 = value if @cgb_ptr.value
+      when 0xFF55 then start_hdma value if @cgb_ptr.value
+      when 0xFF68
+        if @cgb_ptr.value
+          @palette_index = value & 0x3F
+          @auto_increment = value & 0x80 > 0
+        end
+      when 0xFF69
+        if @cgb_ptr.value
+          @pram[@palette_index] = value
+          @palette_index += 1 if @auto_increment
+          @palette_index &= 0x3F
+        end
+      when 0xFF6A
+        if @cgb_ptr.value
+          @obj_palette_index = value & 0x3F
+          @obj_auto_increment = value & 0x80 > 0
+        end
+      when 0xFF6B
+        if @cgb_ptr.value
+          @obj_pram[@obj_palette_index] = value
+          @obj_palette_index += 1 if @obj_auto_increment
+          @obj_palette_index &= 0x3F
+        end
+      else raise "Writing to invalid ppu register: #{hex_str index.to_u16!}"
+      end
+    end
+
+    # LCD Control Register
+
+    def lcd_enabled? : Bool
+      @lcd_control & (0x1 << 7) != 0
+    end
+
+    def window_tile_map : UInt8
+      @lcd_control & (0x1 << 6)
+    end
+
+    def window_enabled? : Bool
+      @lcd_control & (0x1 << 5) != 0
+    end
+
+    def bg_window_tile_data : UInt8
+      @lcd_control & (0x1 << 4)
+    end
+
+    def bg_tile_map : UInt8
+      @lcd_control & (0x1 << 3)
+    end
+
+    def sprite_height
+      @lcd_control & (0x1 << 2) != 0 ? 16 : 8
+    end
+
+    def sprite_enabled? : Bool
+      @lcd_control & (0x1 << 1) != 0
+    end
+
+    def bg_display? : Bool
+      @lcd_control & 0x1 != 0
+    end
+
+    # LCD Status Register
+
+    def coincidence_interrupt_enabled : Bool
+      @lcd_status & (0x1 << 6) != 0
+    end
+
+    def oam_interrupt_enabled : Bool
+      @lcd_status & (0x1 << 5) != 0
+    end
+
+    def vblank_interrupt_enabled : Bool
+      @lcd_status & (0x1 << 4) != 0
+    end
+
+    def hblank_interrupt_enabled : Bool
+      @lcd_status & (0x1 << 3) != 0
+    end
+
+    def coincidence_flag : Bool
+      @lcd_status & (0x1 << 2) != 0
+    end
+
+    def coincidence_flag=(on : Bool) : Nil
+      @lcd_status = (@lcd_status & ~(0x1 << 2)) | (on ? (0x1 << 2) : 0)
+    end
+
+    def mode_flag : UInt8
+      @lcd_status & 0x3
+    end
+
+    def mode_flag=(mode : UInt8)
+      step_hdma if mode == 0 && @hdma_active
+      @first_line = false if @first_line && mode_flag == 0 && mode == 2
+      @window_trigger = false if mode == 1
+      @lcd_status = (@lcd_status & 0b11111100) | mode
+      handle_stat_interrupt
+    end
+
+    # palettes
+
+    def palette_to_array(palette : UInt8) : Array(UInt8)
+      [palette & 0x3, (palette >> 2) & 0x3, (palette >> 4) & 0x3, (palette >> 6) & 0x3]
+    end
+
+    def palette_from_array(palette_array : Array(UInt8)) : UInt8
+      palette_array.each_with_index.reduce(0x00_u8) do |palette, (color, idx)|
+        palette | color << (idx * 2)
+      end
+    end
+
+    def write_png : Nil
+      @gb.display.write_png @framebuffer
+    end
+  end
+end
diff --git a/src/crab/gb/scanline_ppu.cr b/src/crab/gb/scanline_ppu.cr
index fb67403..5aa3f9d 100644
--- a/src/crab/gb/scanline_ppu.cr
+++ b/src/crab/gb/scanline_ppu.cr
@@ -57,9 +57,9 @@ module GB
           color = (msb << 1) | lsb
           @scanline_color_vals[x] = {color, @vram[1][tile_num_addr] & 0x80 > 0}
           if @cgb_ptr.value
-            @framebuffer[Display::WIDTH * @ly + x] = @palettes[@vram[1][tile_num_addr] & 0b111][color]
+            @framebuffer[Display::WIDTH * @ly + x] = @pram.to_unsafe.as(UInt16*)[4 * (@vram[1][tile_num_addr] & 0b111) + color]
           else
-            @framebuffer[Display::WIDTH * @ly + x] = @palettes[0][@bgp[color]]
+            @framebuffer[Display::WIDTH * @ly + x] = @pram.to_unsafe.as(UInt16*)[@bgp[color]]
           end
         elsif bg_display? || @cgb_ptr.value
           tile_num_addr = background_map + (((x + @scx) >> 3) & 0x1F) + ((((@ly.to_u16 + @scy) >> 3) * 32) & 0x3FF)
@@ -84,9 +84,9 @@ module GB
           color = (msb << 1) | lsb
           @scanline_color_vals[x] = {color, @vram[1][tile_num_addr] & 0x80 > 0}
           if @cgb_ptr.value
-            @framebuffer[Display::WIDTH * @ly + x] = @palettes[@vram[1][tile_num_addr] & 0b111][color]
+            @framebuffer[Display::WIDTH * @ly + x] = @pram.to_unsafe.as(UInt16*)[4 * (@vram[1][tile_num_addr] & 0b111) + color]
           else
-            @framebuffer[Display::WIDTH * @ly + x] = @palettes[0][@bgp[color]]
+            @framebuffer[Display::WIDTH * @ly + x] = @pram.to_unsafe.as(UInt16*)[@bgp[color]]
           end
         end
       end
@@ -112,12 +112,12 @@ module GB
                 # objects are always on top of bg/window color 0
                 # objects are on top of bg/window colors 1-3 if bg_priority and object priority are both unset
                 if !bg_display? || @scanline_color_vals[x][0] == 0 || (!@scanline_color_vals[x][1] && sprite.priority == 0)
-                  @framebuffer[Display::WIDTH * @ly + x] = @obj_palettes[sprite.cgb_palette_number][color]
+                  @framebuffer[Display::WIDTH * @ly + x] = @obj_pram.to_unsafe.as(UInt16*)[4 * sprite.cgb_palette_number + color]
                 end
               else
                 if sprite.priority == 0 || @scanline_color_vals[x][0] == 0
                   palette = sprite.dmg_palette_number == 0 ? @obp0 : @obp1
-                  @framebuffer[Display::WIDTH * @ly + x] = @obj_palettes[0][palette[color]]
+                  @framebuffer[Display::WIDTH * @ly + x] = @obj_pram.to_unsafe.as(UInt16*)[palette[color]]
                 end
               end
             end