diff --git a/src/main/kc/include/veralib.h b/src/main/kc/include/veralib.h
index 89b2fe104..28e81f7ce 100644
--- a/src/main/kc/include/veralib.h
+++ b/src/main/kc/include/veralib.h
@@ -35,6 +35,12 @@ byte* vera_layer_hscroll_h[2] = {VERA_L0_HSCROLL_H, VERA_L1_HSCROLL_H};
 byte vera_layer_textcolor[2] = {WHITE, WHITE};
 byte vera_layer_backcolor[2] = {BLUE, BLUE};
 
+// --- VERA addressing ---
+
+void vera_vram_bank_offset(byte bank, word offset, byte incr);
+void vera_vram_address0(dword bankaddr, byte incr);
+void vera_vram_address1(dword bankaddr, byte incr);
+
 // --- VERA active display management ---
 
 void vera_display_set_scale_none();
@@ -42,6 +48,8 @@ void vera_display_set_scale_double();
 void vera_display_set_scale_triple();
 byte vera_display_get_hscale();
 byte vera_display_get_vscale();
+word vera_display_get_height();
+word vera_display_get_width();
 
 // --- VERA LAYERS ---
 
@@ -50,11 +58,26 @@ byte vera_display_get_vscale();
 // - config: Specifies the modes which are specified using T256C / 'Bitmap Mode' / 'Color Depth'.
 void vera_layer_set_config(byte layer, byte config);
 
-// Set the configuration of the layer.
+
+// Get the configuration of the layer.
 // - layer: Value of 0 or 1.
-// - config: Specifies the modes which are specified using T256C / 'Bitmap Mode' / 'Color Depth'.
+// - return: Specifies the modes which are specified using T256C / 'Bitmap Mode' / 'Color Depth'.
 byte vera_layer_get_config(byte layer);
 
+
+// Set the configuration of the layer text color mode.
+// - layer: Value of 0 or 1.
+// - color_mode: Specifies the color mode to be VERA_LAYER_CONFIG_16 or VERA_LAYER_CONFIG_256 for text mode.
+void vera_layer_set_text_color_mode( byte layer, byte color_mode );
+
+// Set the configuration of the layer to bitmap mode.
+// - layer: Value of 0 or 1.
+void vera_layer_set_bitmap_mode( byte layer );
+
+// Set the configuration of the layer to tilemap mode.
+// - layer: Value of 0 or 1.
+void vera_layer_set_tilemap_mode( byte layer );
+
 // Set the map width or height of the layer.
 // - layer: Value of 0 or 1.
 inline void vera_layer_set_width_32(byte layer);
@@ -66,41 +89,72 @@ inline void vera_layer_set_height_64(byte layer);
 inline void vera_layer_set_height_128(byte layer);
 inline void vera_layer_set_height_256(byte layer);
 
+// Get the map width of the layer.
+// - layer: Value of 0 or 1.
+word vera_layer_get_width(byte layer);
+
+// Get the map height of the layer.
+// - layer: Value of 0 or 1.
+word vera_layer_get_height(byte layer);
+
+
+// Set the color depth of the layer in bit per pixel (BPP) to 1.
+// - layer: Value of 0 or 1.
+inline void vera_layer_set_color_depth_1BPP(byte layer);
+
+// Set the color depth of the layer in bit per pixel (BPP) to 1.
+// - layer: Value of 0 or 1.
+inline void vera_layer_set_color_depth_2BPP(byte layer);
+
+// Set the color depth of the layer in bit per pixel (BPP) to 1.
+// - layer: Value of 0 or 1.
+inline void vera_layer_set_color_depth_4BPP(byte layer);
+
+// Set the color depth of the layer in bit per pixel (BPP) to 1.
+// - layer: Value of 0 or 1.
+inline void vera_layer_set_color_depth_8BPP(byte layer);
+
+// Get the color depth of the layer.
+// - layer: Value of 0 or 1.
+// - return: 0 = 1 color, 1 = 2 colors, 2 = 4 colors or 3 = 8 colors.
+inline byte vera_layer_get_color_depth(byte layer);
+
 // Enable the layer to be displayed on the screen.
 // - layer: 0 or 1.
-void vera_layer_show(byte layer);
+inline void vera_layer_show(byte layer);
 
 // Disable the layer to be displayed on the screen.
 // - layer: 0 or 1.
-void vera_layer_hide(byte layer);
+inline void vera_layer_hide(byte layer);
 
 // Is the layer shown on the screen?
 // - returns: 1 if layer is displayed on the screen, 0 if not.
-byte vera_layer_is_visible(byte layer);
+inline byte vera_layer_is_visible(byte layer);
 
-// Set the base of the map for the layer with which the conio will interact.
+
+// Set the base of the map layer with which the conio will interact.
 // - layer: Value of 0 or 1.
 // - mapbase: Specifies the base address of the tile map.
 //   Note that the register only specifies bits 16:9 of the address,
 //   so the resulting address in the VERA VRAM is always aligned to a multiple of 512 bytes.
 void vera_layer_set_mapbase(byte layer, byte mapbase);
 
-// Get the base of the map for the layer with which the conio will interact.
-// - layer: Value of 0 or 1.
-// - return: Returns the base address of the tile map.
-//   Note that the register is a byte, specifying only bits 16:9 of the address,
-//   so the resulting address in the VERA VRAM is always aligned to a multiple of 512 bytes!
-byte vera_layer_get_mapbase(byte layer);
-
 // Set the base of the map layer with which the conio will interact.
 // - layer: Value of 0 or 1.
-// - mapbase_address: A dword typed address (4 bytes), that specifies the full address of the map base.
+// - mapbase_address: a dword typed address (4 bytes), that specifies the full address of the map base.
 //   The function does the translation from the dword that contains the 17 bit address,
 //   to the respective mapbase vera register.
 //   Note that the register only specifies bits 16:9 of the address,
 //   so the resulting address in the VERA VRAM is always aligned to a multiple of 512 bytes.
 void vera_layer_set_mapbase_address(byte layer, dword mapbase_address);
 
+// Get the base of the map layer with which the conio will interact.
+// - layer: Value of 0 or 1.
+// - return: Returns the base address of the tile map.
+//   Note that the register is a byte, specifying only bits 16:9 of the address,
+//   so the resulting address in the VERA VRAM is always aligned to a multiple of 512 bytes.
+byte vera_layer_get_mapbase(byte layer);
+
 // Get the map base address of the tiles for the layer.
 // - layer: Value of 0 or 1.
 // - return: Specifies the map base address of the layer, which is returned as a dword.
@@ -108,6 +162,20 @@ void vera_layer_set_mapbase_address(byte layer, dword mapbase_address);
 //   so the resulting address in the VERA VRAM is always aligned to a multiple of 512 bytes!
 dword vera_layer_get_mapbase_address(byte layer);
 
+// Get the map base bank of the tiles for the layer.
+// - layer: Value of 0 or 1.
+// - return: Bank in vera vram.
+byte vera_layer_get_mapbase_bank(byte layer);
+
+// Get the map base lower 16-bit address (offset) of the tiles for the layer.
+// - layer: Value of 0 or 1.
+// - return: Offset in vera vram of the specified bank.
+word vera_layer_get_mapbase_offset(byte layer);
+
+
+
+
+
 // Set the base of the tiles for the layer with which the conio will interact.
 // - layer: Value of 0 or 1.
 // - tilebase: Specifies the base address of the tile map.
@@ -115,9 +183,9 @@ dword vera_layer_get_mapbase_address(byte layer);
 //   so the resulting address in the VERA VRAM is always aligned to a multiple of 2048 bytes!
 void vera_layer_set_tilebase(byte layer, byte tilebase);
 
-// Set the base of the tiles for the layer with which the conio will interact.
+// Set the base address of the tiles for the layer with which the conio will interact.
 // - layer: Value of 0 or 1.
-// - tilebase_address: A dword typed address (4 bytes), that specifies the base address of the tile map.
+// - tilebase_address: a dword typed address (4 bytes), that specifies the base address of the tile map.
 //   The function does the translation from the dword that contains the 17 bit address,
 //   to the respective tilebase vera register.
 //   Note that the resulting vera register holds only specifies bits 16:11 of the address,
@@ -131,11 +199,19 @@ void vera_layer_set_tilebase_address(byte layer, dword tilebase_address);
 //   so the resulting address in the VERA VRAM is always aligned to a multiple of 2048 bytes!
 byte vera_layer_get_tilebase(byte layer);
 
+// Get the tile base address of the tiles for the layer.
+// - layer: Value of 0 or 1.
+// - return: Specifies the base address of the tile map, which is calculated as an unsigned long int.
+//   Note that the register only specifies bits 16:11 of the address,
+//   so the resulting address in the VERA VRAM is always aligned to a multiple of 2048 bytes!
+dword vera_layer_get_tilebase_address(byte layer);
+
+// --- VERA layer color management ---
 
 // Set the front color for text output. The old front text color setting is returned.
 // - layer: Value of 0 or 1.
-// - color: a 4 bit value ( decimal between 0 and 15).
-//   This will only work when the VERA is in 16 color mode!
+// - color: a 4 bit value ( decimal between 0 and 15) when the VERA works in 16x16 color text mode.
+//   An 8 bit value (decimal between 0 and 255) when the VERA works in 256 text mode.
 //   Note that on the VERA, the transparent color has value 0.
 byte vera_layer_set_textcolor(byte layer, byte color);
 
@@ -177,6 +253,19 @@ inline void vera_layer_set_horizontal_scroll(byte layer, word scroll);
 // - scroll: A value between 0 and 4096.
 inline void vera_layer_set_vertical_scroll(byte layer, word scroll);
 
+// --- VERA layer technical functions to quickly shift rows.
+
+// Get the bit shift value required to skip a whole line fast.
+// - layer: Value of 0 or 1.
+// - return: Rowshift value to calculate fast from a y value to line offset in tile mode.
+byte vera_layer_get_rowshift(byte layer);
+
+// Get the value required to skip a whole line fast.
+// - layer: Value of 0 or 1.
+// - return: Skip value to calculate fast from a y value to line offset in tile mode.
+word vera_layer_get_rowskip(byte layer);
+
+
 // Set a vera layer in tile mode and configure the:
 // - layer: Value of 0 or 1.
 // - mapbase_address: A dword typed address (4 bytes), that specifies the full address of the map base.
@@ -196,3 +285,42 @@ inline void vera_layer_set_vertical_scroll(byte layer, word scroll);
 // - color_depth: The color depth in bits per pixel (BPP), which can be 1, 2, 4 or 8.
 void vera_layer_mode_tile(byte layer, dword mapbase_address, dword tilebase_address, word mapwidth, word mapheight, byte tilewidth, byte tileheight, byte color_depth );
 
+
+// Set a vera layer in text mode and configure the:
+// - layer: Value of 0 or 1.
+// - mapbase_address: A dword typed address (4 bytes), that specifies the full address of the map base.
+//   The function does the translation from the dword that contains the 17 bit address,
+//   to the respective mapbase vera register.
+//   Note that the register only specifies bits 16:9 of the address,
+//   so the resulting address in the VERA VRAM is always aligned to a multiple of 512 bytes.
+// - tilebase_address: A dword typed address (4 bytes), that specifies the base address of the tile map.
+//   The function does the translation from the dword that contains the 17 bit address,
+//   to the respective tilebase vera register.
+//   Note that the resulting vera register holds only specifies bits 16:11 of the address,
+//   so the resulting address in the VERA VRAM is always aligned to a multiple of 2048 bytes!
+// - mapwidth: The width of the map in number of tiles.
+// - mapheight: The height of the map in number of tiles.
+// - tilewidth: The width of a tile, which can be 8 or 16 pixels.
+// - tileheight: The height of a tile, which can be 8 or 16 pixels.
+// - color_mode: The color mode, which can be 16 or 256.
+void vera_layer_mode_text(byte layer, dword mapbase_address, dword tilebase_address, word mapwidth, word mapheight, byte tilewidth, byte tileheight, word color_mode );
+
+// Set a vera layer in bitmap mode and configure the:
+// - layer: Value of 0 or 1.
+// - mapbase_address: A dword typed address (4 bytes), that specifies the full address of the map base.
+//   The function does the translation from the dword that contains the 17 bit address,
+//   to the respective mapbase vera register.
+//   Note that the register only specifies bits 16:9 of the address,
+//   so the resulting address in the VERA VRAM is always aligned to a multiple of 512 bytes.
+// - tilebase_address: A dword typed address (4 bytes), that specifies the base address of the tile map.
+//   The function does the translation from the dword that contains the 17 bit address,
+//   to the respective tilebase vera register.
+//   Note that the resulting vera register holds only specifies bits 16:11 of the address,
+//   so the resulting address in the VERA VRAM is always aligned to a multiple of 2048 bytes!
+// - mapwidth: The width of the map in number of tiles.
+// - mapheight: The height of the map in number of tiles.
+// - tilewidth: The width of a tile, which can be 8 or 16 pixels.
+// - tileheight: The height of a tile, which can be 8 or 16 pixels.
+// - color_mode: The color mode, which can be 16 or 256.
+void vera_layer_mode_bitmap(byte layer, dword bitmap_address, word mapwidth, word color_depth );
+
diff --git a/src/main/kc/lib/veralib.c b/src/main/kc/lib/veralib.c
index 4e3f132ff..467dc91e4 100644
--- a/src/main/kc/lib/veralib.c
+++ b/src/main/kc/lib/veralib.c
@@ -127,15 +127,14 @@ void vera_layer_set_config(byte layer, byte config) {
     *addr = config;
 }
 
-// Set the configuration of the layer.
+// Get the configuration of the layer.
 // - layer: Value of 0 or 1.
-// - config: Specifies the modes which are specified using T256C / 'Bitmap Mode' / 'Color Depth'.
+// - return: Specifies the modes which are specified using T256C / 'Bitmap Mode' / 'Color Depth'.
 byte vera_layer_get_config(byte layer) {
     byte* config = vera_layer_config[layer];
     return *config;
 }
-
-// Set the configuration of the layer.
+// Set the configuration of the layer text color mode.
 // - layer: Value of 0 or 1.
 // - color_mode: Specifies the color mode to be VERA_LAYER_CONFIG_16 or VERA_LAYER_CONFIG_256 for text mode.
 void vera_layer_set_text_color_mode( byte layer, byte color_mode ) {
@@ -204,7 +203,7 @@ inline void vera_layer_set_height_256(byte layer) {
     *addr |= VERA_LAYER_HEIGHT_256;
 }
 
-// Get the map width or height of the layer.
+// Get the map width of the layer.
 // - layer: Value of 0 or 1.
 word vera_layer_get_width(byte layer) {
     byte* config = vera_layer_config[layer];
@@ -212,29 +211,40 @@ word vera_layer_get_width(byte layer) {
     return VERA_LAYER_WIDTH[ (*config & mask) >> 4];
 }
 
+// Get the map height of the layer.
+// - layer: Value of 0 or 1.
 word vera_layer_get_height(byte layer) {
     byte* config = vera_layer_config[layer];
     byte mask = VERA_LAYER_HEIGHT_MASK;
     return VERA_LAYER_HEIGHT[ (*config & mask) >> 6];
 }
 
-// Set the color depth of the layer in terms of bit per pixel (BPP) of the tile base.
+// Set the color depth of the layer in bit per pixel (BPP) to 1.
 // - layer: Value of 0 or 1.
 inline void vera_layer_set_color_depth_1BPP(byte layer) {
     byte* addr = vera_layer_config[layer];
     *addr &= ~VERA_LAYER_COLOR_DEPTH_MASK;
     *addr |= VERA_LAYER_COLOR_DEPTH_1BPP;
 }
+
+// Set the color depth of the layer in bit per pixel (BPP) to 1.
+// - layer: Value of 0 or 1.
 inline void vera_layer_set_color_depth_2BPP(byte layer) {
     byte* addr = vera_layer_config[layer];
     *addr &= ~VERA_LAYER_COLOR_DEPTH_MASK;
     *addr |= VERA_LAYER_COLOR_DEPTH_2BPP;
 }
+
+// Set the color depth of the layer in bit per pixel (BPP) to 1.
+// - layer: Value of 0 or 1.
 inline void vera_layer_set_color_depth_4BPP(byte layer) {
     byte* addr = vera_layer_config[layer];
     *addr &= ~VERA_LAYER_COLOR_DEPTH_MASK;
     *addr |= VERA_LAYER_COLOR_DEPTH_4BPP;
 }
+
+// Set the color depth of the layer in bit per pixel (BPP) to 1.
+// - layer: Value of 0 or 1.
 inline void vera_layer_set_color_depth_8BPP(byte layer) {
     byte* addr = vera_layer_config[layer];
     *addr &= ~VERA_LAYER_COLOR_DEPTH_MASK;
@@ -244,10 +254,9 @@ inline void vera_layer_set_color_depth_8BPP(byte layer) {
 // Get the color depth of the layer.
 // - layer: Value of 0 or 1.
 // - return: 0 = 1 color, 1 = 2 colors, 2 = 4 colors or 3 = 8 colors.
-byte vera_layer_get_color_depth(byte layer) {
+inline byte vera_layer_get_color_depth(byte layer) {
     byte* config = vera_layer_config[layer];
-    byte mask = (byte)VERA_LAYER_COLOR_DEPTH_MASK;
-    return *config & mask;
+    return (*config & VERA_LAYER_COLOR_DEPTH_MASK);
 }
 
 // Enable the layer to be displayed on the screen.
@@ -263,7 +272,6 @@ inline void vera_layer_hide(byte layer) {
     *VERA_DC_VIDEO &= ~vera_layer_enable[layer];
 }
 
-
 // Is the layer shown on the screen?
 // - returns: 1 if layer is displayed on the screen, 0 if not.
 inline byte vera_layer_is_visible(byte layer) {