diff --git a/src/mame/drivers/tiamc1.cpp b/src/mame/drivers/tiamc1.cpp
index 7b59b5be424..591ab1edb0b 100644
--- a/src/mame/drivers/tiamc1.cpp
+++ b/src/mame/drivers/tiamc1.cpp
@@ -113,7 +113,6 @@
      - Use machine/pit8253.c in sound
      - Check sprites priorities on the real hardware
      - Check vertical background scrolling on the real hardware
-     - What charset control is used for?
      - Kot Rybolov viewable area size likely controlled by pit8253 timers 0 and 1, used in test mode only
 
 */
@@ -168,7 +167,7 @@ static ADDRESS_MAP_START( tiamc1_io_map, AS_IO, 8, tiamc1_state )
 	AM_RANGE(0xbc, 0xbc) AM_WRITE(tiamc1_bg_vshift_w)/* background V scroll */
 	AM_RANGE(0xbd, 0xbd) AM_WRITE(tiamc1_bg_hshift_w)/* background H scroll */
 	AM_RANGE(0xbe, 0xbe) AM_WRITE(tiamc1_bankswitch_w) /* VRAM selector */
-	AM_RANGE(0xbf, 0xbf) AM_WRITENOP                 /* charset control */
+	AM_RANGE(0xbf, 0xbf) AM_WRITE(tiamc1_bg_bplctrl_w) /* charset control */
 	AM_RANGE(0xc0, 0xc3) AM_DEVWRITE("2x8253", tiamc1_sound_device, tiamc1_timer0_w)   /* timer 0 */
 	AM_RANGE(0xd0, 0xd3) AM_DEVREADWRITE("kr580vv55a", i8255_device, read, write)    /* input ports + coin counters & lockout */
 	AM_RANGE(0xd4, 0xd7) AM_DEVWRITE("2x8253", tiamc1_sound_device, tiamc1_timer1_w)   /* timer 1 */
@@ -236,8 +235,8 @@ static INPUT_PORTS_START( gorodki )
 	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_SPECIAL )   /* OUT:game counter */
 	PORT_BIT( 0x08, IP_ACTIVE_LOW, IPT_UNKNOWN )    /* RAZR ??? */
 	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_COIN1 )
-	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_BUTTON1 ) PORT_PLAYER(1) // right button
-	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_BUTTON2 ) PORT_PLAYER(1) // left button
+	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_BUTTON2 ) PORT_PLAYER(1) // right button
+	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_BUTTON1 ) PORT_PLAYER(1) // left button
 	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_CUSTOM ) PORT_VBLANK("screen")
 INPUT_PORTS_END
 
@@ -337,7 +336,7 @@ static MACHINE_CONFIG_START( tiamc1, tiamc1_state )
 	MCFG_SCREEN_PALETTE("palette")
 
 	MCFG_GFXDECODE_ADD("gfxdecode", "palette", tiamc1)
-	MCFG_PALETTE_ADD("palette", 16)
+	MCFG_PALETTE_ADD("palette", 32)
 	MCFG_PALETTE_INIT_OWNER(tiamc1_state, tiamc1)
 
 	/* sound hardware */
diff --git a/src/mame/includes/tiamc1.h b/src/mame/includes/tiamc1.h
index 2766b994339..513f7c1df5f 100644
--- a/src/mame/includes/tiamc1.h
+++ b/src/mame/includes/tiamc1.h
@@ -22,9 +22,11 @@ public:
 	UINT8 *m_spriteram_y;
 	UINT8 *m_spriteram_a;
 	UINT8 *m_spriteram_n;
+	UINT8 *m_paletteram;
 	UINT8 m_layers_ctrl;
 	UINT8 m_bg_vshift;
 	UINT8 m_bg_hshift;
+	UINT8 m_bg_bplctrl;
 	tilemap_t *m_bg_tilemap1;
 	tilemap_t *m_bg_tilemap2;
 	std::unique_ptr<rgb_t[]> m_palette_ptr;
@@ -37,6 +39,7 @@ public:
 	DECLARE_WRITE8_MEMBER(tiamc1_sprite_n_w);
 	DECLARE_WRITE8_MEMBER(tiamc1_bg_vshift_w);
 	DECLARE_WRITE8_MEMBER(tiamc1_bg_hshift_w);
+	DECLARE_WRITE8_MEMBER(tiamc1_bg_bplctrl_w);
 	DECLARE_WRITE8_MEMBER(tiamc1_palette_w);
 	DECLARE_WRITE8_MEMBER(kot_bankswitch_w);
 	DECLARE_WRITE8_MEMBER(kot_videoram_w);
@@ -56,6 +59,7 @@ public:
 	required_device<palette_device> m_palette;
 private:
 	optional_device<speaker_sound_device> m_speaker;
+	void update_bg_palette();
 };
 
 
diff --git a/src/mame/video/tiamc1.cpp b/src/mame/video/tiamc1.cpp
index d813b0030fb..a87fb5ee31a 100644
--- a/src/mame/video/tiamc1.cpp
+++ b/src/mame/video/tiamc1.cpp
@@ -89,9 +89,24 @@ WRITE8_MEMBER(tiamc1_state::tiamc1_bg_hshift_w)
 	m_bg_hshift = data;
 }
 
+WRITE8_MEMBER(tiamc1_state::tiamc1_bg_bplctrl_w)
+{
+	m_bg_bplctrl = data;
+	update_bg_palette();
+}
+
 WRITE8_MEMBER(tiamc1_state::tiamc1_palette_w)
 {
+	m_paletteram[offset] = data;
 	m_palette->set_pen_color(offset, m_palette_ptr[data]);
+	update_bg_palette();
+}
+
+void tiamc1_state::update_bg_palette()
+{
+	UINT8 bplmask = ((m_bg_bplctrl >> 0) & 1) | ((m_bg_bplctrl >> 1) & 2) | ((m_bg_bplctrl >> 2) & 4) | ((m_bg_bplctrl >> 3) & 8);
+	for (int i = 0; i < 16; i++)
+		m_palette->set_pen_color(i + 16, m_palette_ptr[m_paletteram[i | bplmask]]);
 }
 
 PALETTE_INIT_MEMBER(tiamc1_state, tiamc1)
@@ -139,7 +154,7 @@ TILE_GET_INFO_MEMBER(tiamc1_state::get_bg2_tile_info)
 
 void tiamc1_state::video_start()
 {
-	m_videoram = make_unique_clear<UINT8[]>(0x3040);
+	m_videoram = make_unique_clear<UINT8[]>(0x3050);
 
 		m_charram = m_videoram.get() + 0x0800;     /* Ram is banked */
 		m_tileram = m_videoram.get() + 0x0000;
@@ -148,8 +163,9 @@ void tiamc1_state::video_start()
 	m_spriteram_x = m_videoram.get() + 0x3010;
 	m_spriteram_n = m_videoram.get() + 0x3020;
 	m_spriteram_a = m_videoram.get() + 0x3030;
+	m_paletteram  = m_videoram.get() + 0x3040;
 
-	save_pointer(NAME(m_videoram.get()), 0x3040);
+	save_pointer(NAME(m_videoram.get()), 0x3050);
 
 	m_bg_tilemap1 = &machine().tilemap().create(m_gfxdecode, tilemap_get_info_delegate(FUNC(tiamc1_state::get_bg1_tile_info),this), TILEMAP_SCAN_ROWS,
 			8, 8, 32, 32);
@@ -158,9 +174,12 @@ void tiamc1_state::video_start()
 			8, 8, 32, 32);
 	m_bg_tilemap1->set_scrolldx(4, 4);
 	m_bg_tilemap2->set_scrolldx(4, 4);
+	m_bg_tilemap1->set_palette_offset(16);
+	m_bg_tilemap2->set_palette_offset(16);
 
 	m_bg_vshift = 0;
 	m_bg_hshift = 0;
+	m_bg_bplctrl = 0;
 
 	save_item(NAME(m_layers_ctrl));
 	save_item(NAME(m_bg_vshift));
@@ -173,14 +192,15 @@ VIDEO_START_MEMBER(tiamc1_state, kot)
 {
 	m_charram = memregion("gfx2")->base();
 
-	m_videoram    = make_unique_clear<UINT8[]>(0x440);
+	m_videoram    = make_unique_clear<UINT8[]>(0x450);
 	m_tileram     = m_videoram.get() + 0x000;
 	m_spriteram_y = m_videoram.get() + 0x400;
 	m_spriteram_x = m_videoram.get() + 0x410;
 	m_spriteram_n = m_videoram.get() + 0x420;
 	m_spriteram_a = m_videoram.get() + 0x430;
+	m_paletteram  = m_videoram.get() + 0x440;
 
-	save_pointer(NAME(m_videoram.get()), 0x440);
+	save_pointer(NAME(m_videoram.get()), 0x450);
 
 	m_bg_tilemap1 = &machine().tilemap().create(m_gfxdecode, tilemap_get_info_delegate(FUNC(tiamc1_state::get_bg1_tile_info), this), TILEMAP_SCAN_ROWS,
 		8, 8, 32, 32);