diff --git a/include/gb.h b/include/gb.h
index 9a981cd..96a26f1 100644
--- a/include/gb.h
+++ b/include/gb.h
@@ -127,6 +127,7 @@ enum {
 #define	GB_PPU_LCDC_TILE_BASE		0x10
 #define	GB_PPU_LCDC_WIN_ENABLE		0x20
 #define	GB_PPU_LCDC_WIN_TILE_MAP	0x40
+#define	GB_PPU_LCDC_ENABLE		0x80
 
 enum {
 	GB_PPU_STAT_MODE_HBLANK = 0,
@@ -169,6 +170,8 @@ typedef struct pixel_fifo_fetcher_t {
 //flags1
 //window x condition triggered
 #define	GB_PIXEL_FIFO_WXC_TRIGGERED	0x8
+//indicates that LCDC_ENABLE bit was fliped
+#define	GB_PIXEL_FIFO_LCDC_SWITCH	0x10
 
 #define	GB_OAM_PALLET	0x10
 #define	GB_OAM_FLIP_X	0x20
diff --git a/include/ragb_sdl.h b/include/ragb_sdl.h
index f196f8e..e0a660b 100644
--- a/include/ragb_sdl.h
+++ b/include/ragb_sdl.h
@@ -8,14 +8,16 @@ typedef struct gb_pixel_buffer_t {
 	SDL_Texture *texture;
 	ut8 *buf;	//buffer containing pixeldata
 	ut32 color[4];	//rgb colors
+	ut32 clear_color;
 	ut16 w;		//x size in pixel
 	ut16 h;		//y size in pixel
 //	ut16 xsf;	//x scale factor for projecting onto the texture
 //	ut16 ysf;	//y scale factor for projecting onto the texture
 } GBPixBuf;
 
-GBPixBuf *gb_pix_buf_new(SDL_Renderer *renderer, ut16 w, ut16 h);
+GBPixBuf *gb_pix_buf_new(SDL_Renderer *renderer, ut16 w, ut16 h, ut32 clear_color);
 void gb_pix_buf_free(GBPixBuf *pb);
 void gb_pix_buf_set_pixel(GBPixBuf *pb, ut16 x, ut16 y, ut8 pixval);
 void gb_pix_buf_set_color(GBPixBuf *pb, ut8 color_idx, ut32 rgb);
+void gb_pix_buf_clear(GBPixBuf *pb);
 #endif
diff --git a/io/ppu.c b/io/ppu.c
index 0fd8baa..b115dad 100644
--- a/io/ppu.c
+++ b/io/ppu.c
@@ -53,9 +53,15 @@ static int __write(RIO *io, RIODesc *desc, const ut8 *buf, int len) {
 	for (i = 0; i < len; i++) {
 		switch (seek) {
 		case GB_PPU_STAT:
-			ppu->buf[GB_PPU_STAT] = (buf[i] & 0xf8) | (ppu->buf[GB_PPU_STAT] & 0x7);
+			ppu->buf[GB_PPU_STAT] = (buf[i] & 0xf8) |
+				(ppu->buf[GB_PPU_STAT] & 0x7);
 		case GB_PPU_LY:
 			break;
+		case GB_PPU_LCDC:
+			if ((ppu->buf[GB_PPU_LCDC] & GB_PPU_LCDC_ENABLE) !=
+				(buf[i] & GB_PPU_LCDC_ENABLE)) {
+				ppu->fifo.flags1 |= GB_PIXEL_FIFO_LCDC_SWITCH;
+			}
 		default:
 			ppu->buf[seek] = buf[i];
 			break;
@@ -114,7 +120,8 @@ GBPPU *gb_ppu_open (RIO *io, SDL_Renderer *renderer) {
 		return NULL;
 	}
 	ppu->reg_fd = desc->fd;
-	ppu->pixbuf = gb_pix_buf_new (renderer, 160, 144);
+	//TODO: use proper clear color
+	ppu->pixbuf = gb_pix_buf_new (renderer, 160, 144, 0xabcdef);
 	if (!ppu->pixbuf) {
 		r_io_desc_close (desc);
 		r_io_fd_close (io, ppu->vram_fd);
@@ -480,14 +487,70 @@ static ut32 gb_ppu_render_continue (GB *gb, ut32 cycles) {
 }
 
 static ut32 gb_ppu_hblank_continue (GB *gb, ut32 cycles) {
+	if (cycles >= gb->ppu->fifo.remaining_cycles) {
+		gb->ppu->buf[GB_PPU_LY]++;
+		gb->ppu->buf[GB_PPU_STAT] &= ~GB_PPU_STAT_MODE_MASK;
+		if (gb->ppu->buf[GB_PPU_LY] == 144) {
+			//launch vblank
+			gb->ppu->buf[GB_PPU_STAT] |= GB_PPU_STAT_MODE_VBLANK;
+			return cycles - gb->ppu->fifo.remaining_cycles;
+		}
+		//launch oam scan
+		gb->ppu->buf[GB_PPU_STAT] |= GB_PPU_STAT_MODE_OAM_SCAN;
+		return cycles - gb->ppu->fifo.remaining_cycles;
+	}
+	gb->ppu->fifo.remaining_cycles -= cycles;
 	return 0;
 }
 
 static ut32 gb_ppu_vblank_continue (GB *gb, ut32 cycles) {
+	const ut32 m = gb->ppu->fifo.remaining_cycles % 456;
+	if (m && m < cycles) {
+		gb->ppu->buf[GB_PPU_LY]++;
+		if (gb->ppu->buf[GB_PPU_LY] == 156) {
+			gb->ppu->buf[GB_PPU_STAT] &= ~GB_PPU_STAT_MODE_MASK;
+			gb->ppu->buf[GB_PPU_STAT] |= GB_PPU_STAT_MODE_OAM_SCAN;
+			return cycles - gb->ppu->fifo.remaining_cycles;
+		}
+	}
+	gb->ppu->fifo.remaining_cycles -= cycles;
 	return 0;
 }
 
 void gb_ppu_continue (GB *gb, ut32 cycles) {
+	if (gb->ppu->fifo.flags1 & GB_PIXEL_FIFO_LCDC_SWITCH) {
+		gb->ppu->fifo.flags1 ^= GB_PIXEL_FIFO_LCDC_SWITCH;
+		RIOMap *map = r_io_map_get (gb->io, gb->ppu->oam_mapid);
+		if (gb->ppu->buf[GB_PPU_LCDC] & GB_PPU_LCDC_ENABLE) {
+			//lcd was switched on
+			//launch oam scan
+			gb->ppu->buf[GB_PPU_LY] = 0;
+			//disable oam access
+			map->perm = 0;
+			gb->ppu->buf[GB_PPU_STAT] &= ~GB_PPU_STAT_MODE_MASK;
+			gb->ppu->buf[GB_PPU_STAT] |= GB_PPU_STAT_MODE_OAM_SCAN;
+			if (gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_INTR_OAM) {
+				gb_interrupts_request (gb, GB_INTERRUPT_STAT);
+			}
+		} else {
+			//lcd was switched off
+			//enable oam and vram access
+			map->perm = R_PERM_RWX;
+			map = r_io_map_get (gb->io, gb->ppu->vram_mapid);
+			map->perm = R_PERM_RWX;
+			//clear screen
+			gb_pix_buf_clear (gb->ppu->pixbuf);
+			return;
+		}
+	}
+	if (!(gb->ppu->buf[GB_PPU_LCDC] & GB_PPU_LCDC_ENABLE)) {
+		return;
+	}
+	if (gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_INTR_LYC) {
+		if (gb->ppu->buf[GB_PPU_LY] == gb->ppu->buf[GB_PPU_LYC]) {
+			gb_interrupts_request (gb, GB_INTERRUPT_STAT);
+		}
+	}
 	while (cycles) {
 		switch (gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_MODE_MASK) {
 		case GB_PPU_STAT_MODE_OAM_SCAN:
@@ -498,16 +561,47 @@ void gb_ppu_continue (GB *gb, ut32 cycles) {
 			break;
 		case GB_PPU_STAT_MODE_RENDER:
 			cycles = gb_ppu_render_continue (gb, cycles);
+			if ((gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_MODE_MASK) == GB_PPU_STAT_MODE_HBLANK) {
+				RIOMap *map = r_io_map_get (gb->io, gb->ppu->oam_mapid);
+				map->perm = R_PERM_RWX;
+				map = r_io_map_get (gb->io, gb->ppu->vram_mapid);
+				map->perm = R_PERM_RWX;
+			}
 			break;
 		case GB_PPU_STAT_MODE_HBLANK:
 			cycles = gb_ppu_hblank_continue (gb, cycles);
+			if ((gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_MODE_MASK) == GB_PPU_STAT_MODE_OAM_SCAN) {
+				RIOMap *oam = r_io_map_get (gb->io, gb->ppu->oam_mapid);
+				oam->perm = 0;
+				if (gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_INTR_OAM) {
+					gb_interrupts_request (gb, GB_INTERRUPT_STAT);
+				}
+			} else if ((gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_MODE_MASK) == GB_PPU_STAT_MODE_VBLANK) {
+				if (gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_INTR_VBLANK) {
+					gb_interrupts_request (gb, GB_INTERRUPT_STAT);
+				}
+				gb_interrupts_request (gb, GB_INTERRUPT_VBLANK);
+				gb->ppu->fifo.remaining_cycles = 4560;
+			}
 			break;
 		case GB_PPU_STAT_MODE_VBLANK:
 			cycles = gb_ppu_vblank_continue (gb, cycles);
+			if ((gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_MODE_MASK) == GB_PPU_STAT_MODE_OAM_SCAN) {
+				gb->ppu->buf[GB_PPU_LY] = 0;
+				RIOMap *oam = r_io_map_get (gb->io, gb->ppu->oam_mapid);
+				oam->perm = 0;
+				if (gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_INTR_OAM) {
+					gb_interrupts_request (gb, GB_INTERRUPT_STAT);
+				}
+			}
 			break;
 		}
 	}
-	//TODO
+	if (gb->ppu->buf[GB_PPU_STAT] & GB_PPU_STAT_INTR_LYC) {
+		if (gb->ppu->buf[GB_PPU_LY] == gb->ppu->buf[GB_PPU_LYC]) {
+			gb_interrupts_request (gb, GB_INTERRUPT_STAT);
+		}
+	}
 }
 
 void gb_ppu_close (GBPPU *ppu, RIO *io) {
diff --git a/sdl/pixbuf.c b/sdl/pixbuf.c
index 3c62273..c7fac5d 100644
--- a/sdl/pixbuf.c
+++ b/sdl/pixbuf.c
@@ -2,7 +2,7 @@
 #include <r_util.h>
 #include <SDL2/SDL.h>
 
-GBPixBuf *gb_pix_buf_new (SDL_Renderer *renderer, ut16 w, ut16 h) {
+GBPixBuf *gb_pix_buf_new (SDL_Renderer *renderer, ut16 w, ut16 h, ut32 clear_color) {
 	if (!renderer || !w || !h) {
 		return NULL;
 	}
@@ -26,6 +26,7 @@ GBPixBuf *gb_pix_buf_new (SDL_Renderer *renderer, ut16 w, ut16 h) {
 	}
 	pb->w = w;
 	pb->h = h;
+	pb->clear_color = clear_color;
 	return pb;
 }
 
@@ -62,3 +63,15 @@ void gb_pix_buf_set_color (GBPixBuf *pb, ut8 color_idx, ut32 rgb) {
 	}
 	pb->color[color_idx & 0x3] = rgb;
 }
+
+void gb_pix_buf_clear (GBPixBuf *pb) {
+	if (!pb) {
+		return;
+	}
+	SDL_Texture *target = SDL_GetRenderTarget (pb->renderer);
+	SDL_SetRenderTarget (pb->renderer, pb->texture);
+	SDL_SetRenderDrawColor (pb->renderer, (pb->clear_color >> 16) & 0xff,
+		(pb->clear_color >> 8) & 0xff, pb->clear_color & 0xff, 0xff);
+	SDL_RenderClear (pb->renderer);
+	SDL_SetRenderTarget (pb->renderer, target);
+}